http://www.flickr.com/photos/chris_malcolm/tags/reddot/ Fri, 16 Mar 2012 18:02:13 -0700 Fri, 16 Mar 2012 18:02:13 -0700 http://www.flickr.com/ http://farm1.staticflickr.com/208/buddyicons/7974576@N06.jpg?1178550629#7974576@N06 http://www.flickr.com/photos/chris_malcolm/tags/reddot/ http://www.flickr.com/photos/chris_malcolm/6988604369/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/6988604369/" title="500mm with red dot sight (side)"><img src="http://farm8.staticflickr.com/7207/6988604369_d7baa113cc_m.jpg" width="240" height="160" alt="500mm with red dot sight (side)" /></a></p> <p>500mm lenses are difficult things to aim, especially when the thing you're trying to find is against a featureless background, and almost impossible if the thing is moving fast, such as a bird in flight. Like a big telescope they need some kind of sighting aid. A red dot gun sight with no magnification is very good, because it allows you to look with both eyes open and see a red dot projected on your target (an optical illusion, not a laser beam :-).<br /> <br /> They're designed to clamp onto a gun sight wedge mount, so some kind of adapter is required. I played with the hot shoe mount, but it was too flexible -- the sight needed re-zeroing at every mount, and was easily knocked out of calibration. The degree of precision required to aim the central focus sensor at the target via the dot also made parallax error a problem on the hot shoe. So I decided to mount it directly on the lens. Least parallax error, plus the geometry of the lens barrel and the sight mount naturally lines it up with the lens. To protect the lens barrel I glued the sight clamp to a cardboard tube slightly too small, slit open to provide a sprung grab on the lens body. The slit also handily accommodates the focus hold button on the lens barrel.<br /> <br /> It works amazingly well! It's now trivially easy to aim the lens at anything very quickly indeed, including birds in flight. Getting the lens to lock focus on a bird is a bit trickier. Without bothering to zero the sight carefully I found that If the flying bird occupies at least 1/10th of the image the AF manages to lock focus quite soon. But tiny birds, or distant birds, often fail to lock just using the red dot sight, and if you drop to viewfinder or live view the view becomes so narrow the bird is easily lost. So experiments with careful calibration and technique are required.<br /> <br /> But initial results are very encouraging! This has suddenly become a VERY much more useful and easily used lens! Although having a gun sight on top of it does reduce one of the advantages of a 500mm reflex lens -- it doesn't look like a long lens, so people are less nervous of it than a foot long lens with a dinner plate objective.<br /> <br /> <br /> DSC05977X</p> Fri, 16 Mar 2012 18:02:13 -0700 2012-03-15T00:16:01-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/6988604369 500mm with red dot sight (side) <p>500mm lenses are difficult things to aim, especially when the thing you're trying to find is against a featureless background, and almost impossible if the thing is moving fast, such as a bird in flight. Like a big telescope they need some kind of sighting aid. A red dot gun sight with no magnification is very good, because it allows you to look with both eyes open and see a red dot projected on your target (an optical illusion, not a laser beam :-).<br /> <br /> They're designed to clamp onto a gun sight wedge mount, so some kind of adapter is required. I played with the hot shoe mount, but it was too flexible -- the sight needed re-zeroing at every mount, and was easily knocked out of calibration. The degree of precision required to aim the central focus sensor at the target via the dot also made parallax error a problem on the hot shoe. So I decided to mount it directly on the lens. Least parallax error, plus the geometry of the lens barrel and the sight mount naturally lines it up with the lens. To protect the lens barrel I glued the sight clamp to a cardboard tube slightly too small, slit open to provide a sprung grab on the lens body. The slit also handily accommodates the focus hold button on the lens barrel.<br /> <br /> It works amazingly well! It's now trivially easy to aim the lens at anything very quickly indeed, including birds in flight. Getting the lens to lock focus on a bird is a bit trickier. Without bothering to zero the sight carefully I found that If the flying bird occupies at least 1/10th of the image the AF manages to lock focus quite soon. But tiny birds, or distant birds, often fail to lock just using the red dot sight, and if you drop to viewfinder or live view the view becomes so narrow the bird is easily lost. So experiments with careful calibration and technique are required.<br /> <br /> But initial results are very encouraging! This has suddenly become a VERY much more useful and easily used lens! Although having a gun sight on top of it does reduce one of the advantages of a 500mm reflex lens -- it doesn't look like a long lens, so people are less nervous of it than a foot long lens with a dinner plate objective.<br /> <br /> <br /> DSC05977X</p> Chris_Malcolm diy reflex 500mm reddot http://www.flickr.com/photos/chris_malcolm/7161852773/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7161852773/" title="MF 2012 Flying Seagull 12"><img src="http://farm9.staticflickr.com/8149/7161852773_11497f74f7_m.jpg" width="240" height="240" alt="MF 2012 Flying Seagull 12" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07454RWX</p> Wed, 06 Jun 2012 19:52:39 -0700 2012-06-03T15:36:38-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7161852773 MF 2012 Flying Seagull 12 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07454RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7161849801/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7161849801/" title="MF 2012 Flying Seagull 2"><img src="http://farm9.staticflickr.com/8025/7161849801_798fda335e_m.jpg" width="240" height="169" alt="MF 2012 Flying Seagull 2" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07347RWX</p> Wed, 06 Jun 2012 19:51:16 -0700 2012-06-03T15:15:30-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7161849801 MF 2012 Flying Seagull 2 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07347RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7347060460/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7347060460/" title="MF 2012 Flying Seagull 7"><img src="http://farm8.staticflickr.com/7231/7347060460_3100b1a798_m.jpg" width="240" height="170" alt="MF 2012 Flying Seagull 7" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07435RWX</p> Wed, 06 Jun 2012 19:51:56 -0700 2012-06-03T15:30:34-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7347060460 MF 2012 Flying Seagull 7 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07435RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7347061566/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7347061566/" title="MF 2012 Flying Seagull 10"><img src="http://farm8.staticflickr.com/7098/7347061566_9e7499d127_m.jpg" width="240" height="170" alt="MF 2012 Flying Seagull 10" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07440RWX</p> Wed, 06 Jun 2012 19:52:25 -0700 2012-06-03T15:30:42-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7347061566 MF 2012 Flying Seagull 10 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07440RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7161852531/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7161852531/" title="MF 2012 Flying Seagull 11"><img src="http://farm8.staticflickr.com/7099/7161852531_e7e592f9fe_m.jpg" width="240" height="240" alt="MF 2012 Flying Seagull 11" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07442RWX</p> Wed, 06 Jun 2012 19:52:32 -0700 2012-06-03T15:30:48-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7161852531 MF 2012 Flying Seagull 11 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07442RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7161850959/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7161850959/" title="MF 2012 Flying Seagull 6"><img src="http://farm8.staticflickr.com/7239/7161850959_0354cfbb62_m.jpg" width="240" height="170" alt="MF 2012 Flying Seagull 6" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07385RWX</p> Wed, 06 Jun 2012 19:51:49 -0700 2012-06-03T15:20:23-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7161850959 MF 2012 Flying Seagull 6 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07385RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7347059608/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7347059608/" title="MF 2012 Flying Seagull 4"><img src="http://farm9.staticflickr.com/8150/7347059608_8381ba9a0a_m.jpg" width="240" height="170" alt="MF 2012 Flying Seagull 4" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07360RWX</p> Wed, 06 Jun 2012 19:51:34 -0700 2012-06-03T15:16:31-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7347059608 MF 2012 Flying Seagull 4 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07360RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7347060842/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7347060842/" title="MF 2012 Flying Seagull 8"><img src="http://farm8.staticflickr.com/7099/7347060842_70cc12f0d7_m.jpg" width="169" height="240" alt="MF 2012 Flying Seagull 8" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07438RWX</p> Wed, 06 Jun 2012 19:52:06 -0700 2012-06-03T15:30:41-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7347060842 MF 2012 Flying Seagull 8 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07438RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7347062358/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7347062358/" title="MF 2012 red football"><img src="http://farm8.staticflickr.com/7100/7347062358_9f9feb7ee1_m.jpg" width="239" height="240" alt="MF 2012 red football" /></a></p> <p>I wondered if my new fast tracking 500mm reflex lens with its red dot gun sight could now be a useful sports action lens. There were some folk kicking this red football around so I tried to catch someone kicking the ball. Looks as though it could have a reasonable stab at catching that kind of sports action, although I suspect generally speaking getting in closer and using a faster shorter lens would be a better idea.<br /> <br /> Original DSC07495RWX</p> Wed, 06 Jun 2012 19:52:47 -0700 2012-06-03T15:45:36-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7347062358 MF 2012 red football <p>I wondered if my new fast tracking 500mm reflex lens with its red dot gun sight could now be a useful sports action lens. There were some folk kicking this red football around so I tried to catch someone kicking the ball. Looks as though it could have a reasonable stab at catching that kind of sports action, although I suspect generally speaking getting in closer and using a faster shorter lens would be a better idea.<br /> <br /> Original DSC07495RWX</p> Chris_Malcolm sport festival reflex football meadows 500mm 2012 reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7347059834/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7347059834/" title="MF 2012 Flying Seagull 5"><img src="http://farm8.staticflickr.com/7074/7347059834_51552f88ea_m.jpg" width="240" height="170" alt="MF 2012 Flying Seagull 5" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07374RWX</p> Wed, 06 Jun 2012 19:51:40 -0700 2012-06-03T15:20:15-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7347059834 MF 2012 Flying Seagull 5 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07374RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7161851937/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7161851937/" title="MF 2012 Flying Seagull 9"><img src="http://farm8.staticflickr.com/7232/7161851937_c1fe07e2c0_m.jpg" width="170" height="240" alt="MF 2012 Flying Seagull 9" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07439RWX</p> Wed, 06 Jun 2012 19:52:14 -0700 2012-06-03T15:30:42-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7161851937 MF 2012 Flying Seagull 9 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07439RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7161849683/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7161849683/" title="MF 2012 Flying Seagull 1"><img src="http://farm8.staticflickr.com/7089/7161849683_940f306047_m.jpg" width="240" height="170" alt="MF 2012 Flying Seagull 1" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07331RWX</p> Wed, 06 Jun 2012 19:51:13 -0700 2012-06-03T15:14:58-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7161849683 MF 2012 Flying Seagull 1 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07331RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/7347059134/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/7347059134/" title="MF 2012 Flying Seagull 3"><img src="http://farm9.staticflickr.com/8146/7347059134_50e721772a_m.jpg" width="240" height="170" alt="MF 2012 Flying Seagull 3" /></a></p> <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07357RWX</p> Wed, 06 Jun 2012 19:51:22 -0700 2012-06-03T15:15:59-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/7347059134 MF 2012 Flying Seagull 3 <p>Taken on a sunny afternoon at the Meadows Festival 2012 with a 500mm reflex. These reflex (mirror or Newtonian) lenses are usually considered to be absolutely useless for catching birds in flight for a number of reasons, the most important of which is the very narrow field of view, especially on a crop sensor camera. It's hard to aim the lens at what you want to look at, and it takes time to find it. So absolutely no chance of catching a bird in flight!<br /> <br /> A red dot gun sight fitted to the lens as a sighter solves that problem. You keep both eyes open, and see a red dot superimposed on the scene. Move the camera to locate the red dot on your chosen target, and it's in the centre of view of the lens, i.e. on the central AF sensor. This can be done so fast that it's possible to track birds in flight. If you have continuous autofocus set and shutter fire only when focus found plus repeat while shutter held down the camera will take a photograph of the flying bird whenever you've managed to hold the red dot on it for long enough for the lens to autofocus.<br /> <br /> My first effort at building the sight was slightly wobbly. <a href="http://www.flickr.com/photos/chris_malcolm/6988604951/">Here's a photograph of it.</a><br /> <br /> The lens and sight kept going out of alignment and had to be recalibrated. A gentle knock would throw calibration off. The application of more glue and some rubber bands firmed the thing up. This afternoon was the first trial of the toughened version. Excellent results! So here by way of demonstration are a dozen shots of seagulls wheeling over the Meadows Festival, attracted by the crowds of messy eaters. All the images have been cropped down to the bird, and size reduced to 67% of the original pixels. The depth of field of this lens is so shallow that it's impossible to get the whole bird in focus. In fact an image filling bird standing side on will have one leg in focus and the other out. So in this kind of wild flight tracking and shooting when focused the focus is more likely to be uselessly on a wing tip as usefully on the body. I'm encouraged by how many well enough focused shots came out despite my being a complete beginner at flying bird photography.<br /> <br /> So I now have a rather good birds-in-flight lens, just by adding a cheap accessory (red dot gun sight) with some DIY bodgery to what is generally regarded as one of the worst possible lenses for catching birds in flight.<br /> <br /> Original DSC07357RWX</p> Chris_Malcolm seagulls birds festival reflex flight meadows 500mm 2012 bif reddot sal500f80 http://www.flickr.com/photos/chris_malcolm/6842482858/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/6842482858/" title="500mm reflex with long lens hood and red dot sight"><img src="http://farm8.staticflickr.com/7049/6842482858_15dea5202c_m.jpg" width="240" height="160" alt="500mm reflex with long lens hood and red dot sight" /></a></p> <p>500mm lenses are difficult things to aim, especially when the thing you're trying to find is against a featureless background, and almost impossible if the thing is moving fast, such as a bird in flight. Like a big telescope they need some kind of sighting aid. A red dot gun sight with no magnification is very good, because it allows you to look with both eyes open and see a red dot projected on your target (an optical illusion, not a laser beam :-).<br /> <br /> They're designed to clamp onto a gun sight wedge mount, so some kind of adapter is required. I played with the hot shoe mount, but it was too flexible -- the sight needed re-zeroing at every mount, and was easily knocked out of calibration. The degree of precision required to aim the central focus sensor at the target via the dot also made parallax error a problem on the hot shoe. So I decided to mount it directly on the lens. Least parallax error, plus the geometry of the lens barrel and the sight mount naturally lines it up with the lens. To protect the lens barrel I glued the sight clamp to a cardboard tube slightly too small, slit open to provide a sprung grab on the lens body. The slit also handily accommodates the focus hold button on the lens barrel.<br /> <br /> It works amazingly well! It's now trivially easy to aim the lens at anything very quickly indeed, including birds in flight. Getting the lens to lock focus on a bird is a bit trickier. Without bothering to zero the sight carefully I found that If the flying bird occupies at least 1/10th of the image the AF manages to lock focus quite soon. But tiny birds, or distant birds, often fail to lock just using the red dot sight, and if you drop to viewfinder or live view the view becomes so narrow the bird is easily lost. So experiments with careful calibration and technique are required.<br /> <br /> But initial results are very encouraging! This has suddenly become a VERY much more useful and easily used lens! Although having a gun sight on top of it does reduce one of the advantages of a 500mm reflex lens -- it doesn't look like a long lens, so people are less nervous of it than a foot long lens with a dinner plate objective.<br /> <br /> Of course if you feel a little inferior at having a much smaller 500mm lens than the big boys you can always add a long lens hood to it. This one is threaded at both ends so allows you to remount the original short rubberised hood on its end. Lengthening the hood is supposed to improve the contrast of reflex lenses, which are inherently flatter and greyer than refractors. in part due to the increased diffraction edge length created by the hole in the middle. So far I've failed to verify this effect, but I haven't yet tested it in provocatively difficult conditions.<br /> <br /> <br /> DSC05981X</p> Fri, 16 Mar 2012 18:02:57 -0700 2012-03-15T00:27:05-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/6842482858 500mm reflex with long lens hood and red dot sight <p>500mm lenses are difficult things to aim, especially when the thing you're trying to find is against a featureless background, and almost impossible if the thing is moving fast, such as a bird in flight. Like a big telescope they need some kind of sighting aid. A red dot gun sight with no magnification is very good, because it allows you to look with both eyes open and see a red dot projected on your target (an optical illusion, not a laser beam :-).<br /> <br /> They're designed to clamp onto a gun sight wedge mount, so some kind of adapter is required. I played with the hot shoe mount, but it was too flexible -- the sight needed re-zeroing at every mount, and was easily knocked out of calibration. The degree of precision required to aim the central focus sensor at the target via the dot also made parallax error a problem on the hot shoe. So I decided to mount it directly on the lens. Least parallax error, plus the geometry of the lens barrel and the sight mount naturally lines it up with the lens. To protect the lens barrel I glued the sight clamp to a cardboard tube slightly too small, slit open to provide a sprung grab on the lens body. The slit also handily accommodates the focus hold button on the lens barrel.<br /> <br /> It works amazingly well! It's now trivially easy to aim the lens at anything very quickly indeed, including birds in flight. Getting the lens to lock focus on a bird is a bit trickier. Without bothering to zero the sight carefully I found that If the flying bird occupies at least 1/10th of the image the AF manages to lock focus quite soon. But tiny birds, or distant birds, often fail to lock just using the red dot sight, and if you drop to viewfinder or live view the view becomes so narrow the bird is easily lost. So experiments with careful calibration and technique are required.<br /> <br /> But initial results are very encouraging! This has suddenly become a VERY much more useful and easily used lens! Although having a gun sight on top of it does reduce one of the advantages of a 500mm reflex lens -- it doesn't look like a long lens, so people are less nervous of it than a foot long lens with a dinner plate objective.<br /> <br /> Of course if you feel a little inferior at having a much smaller 500mm lens than the big boys you can always add a long lens hood to it. This one is threaded at both ends so allows you to remount the original short rubberised hood on its end. Lengthening the hood is supposed to improve the contrast of reflex lenses, which are inherently flatter and greyer than refractors. in part due to the increased diffraction edge length created by the hole in the middle. So far I've failed to verify this effect, but I haven't yet tested it in provocatively difficult conditions.<br /> <br /> <br /> DSC05981X</p> Chris_Malcolm diy reflex 500mm reddot http://www.flickr.com/photos/chris_malcolm/6988604951/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/6988604951/" title="500mm reflex with red dot sight (angle)"><img src="http://farm8.staticflickr.com/7044/6988604951_7a789bd4c3_m.jpg" width="240" height="160" alt="500mm reflex with red dot sight (angle)" /></a></p> <p>500mm lenses are difficult things to aim, especially when the thing you're trying to find is against a featureless background, and almost impossible if the thing is moving fast, such as a bird in flight. Like a big telescope they need some kind of sighting aid. A red dot gun sight with no magnification is very good, because it allows you to look with both eyes open and see a red dot projected on your target (an optical illusion, not a laser beam :-).<br /> <br /> They're designed to clamp onto a gun sight wedge mount, so some kind of adapter is required. I played with the hot shoe mount, but it was too flexible -- the sight needed re-zeroing at every mount, and was easily knocked out of calibration. The degree of precision required to aim the central focus sensor at the target via the dot also made parallax error a problem on the hot shoe. So I decided to mount it directly on the lens. Least parallax error, plus the geometry of the lens barrel and the sight mount naturally lines it up with the lens. To protect the lens barrel I glued the sight clamp to a cardboard tube slightly too small, slit open to provide a sprung grab on the lens body. The slit also handily accommodates the focus hold button on the lens barrel.<br /> <br /> It works amazingly well! It's now trivially easy to aim the lens at anything very quickly indeed, including birds in flight. Getting the lens to lock focus on a bird is a bit trickier. Without bothering to zero the sight carefully I found that If the flying bird occupies at least 1/10th of the image the AF manages to lock focus quite soon. But tiny birds, or distant birds, often fail to lock just using the red dot sight, and if you drop to viewfinder or live view the view becomes so narrow the bird is easily lost. So experiments with careful calibration and technique are required.<br /> <br /> But initial results are very encouraging! This has suddenly become a VERY much more useful and easily used lens! Although having a gun sight on top of it does reduce one of the advantages of a 500mm reflex lens -- it doesn't look like a long lens, so people are less nervous of it than a foot long lens with a dinner plate objective.<br /> <br /> DSC05979X</p> Fri, 16 Mar 2012 18:02:39 -0700 2012-03-15T00:20:22-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/6988604951 500mm reflex with red dot sight (angle) <p>500mm lenses are difficult things to aim, especially when the thing you're trying to find is against a featureless background, and almost impossible if the thing is moving fast, such as a bird in flight. Like a big telescope they need some kind of sighting aid. A red dot gun sight with no magnification is very good, because it allows you to look with both eyes open and see a red dot projected on your target (an optical illusion, not a laser beam :-).<br /> <br /> They're designed to clamp onto a gun sight wedge mount, so some kind of adapter is required. I played with the hot shoe mount, but it was too flexible -- the sight needed re-zeroing at every mount, and was easily knocked out of calibration. The degree of precision required to aim the central focus sensor at the target via the dot also made parallax error a problem on the hot shoe. So I decided to mount it directly on the lens. Least parallax error, plus the geometry of the lens barrel and the sight mount naturally lines it up with the lens. To protect the lens barrel I glued the sight clamp to a cardboard tube slightly too small, slit open to provide a sprung grab on the lens body. The slit also handily accommodates the focus hold button on the lens barrel.<br /> <br /> It works amazingly well! It's now trivially easy to aim the lens at anything very quickly indeed, including birds in flight. Getting the lens to lock focus on a bird is a bit trickier. Without bothering to zero the sight carefully I found that If the flying bird occupies at least 1/10th of the image the AF manages to lock focus quite soon. But tiny birds, or distant birds, often fail to lock just using the red dot sight, and if you drop to viewfinder or live view the view becomes so narrow the bird is easily lost. So experiments with careful calibration and technique are required.<br /> <br /> But initial results are very encouraging! This has suddenly become a VERY much more useful and easily used lens! Although having a gun sight on top of it does reduce one of the advantages of a 500mm reflex lens -- it doesn't look like a long lens, so people are less nervous of it than a foot long lens with a dinner plate objective.<br /> <br /> DSC05979X</p> Chris_Malcolm diy reflex 500mm reddot http://www.flickr.com/photos/chris_malcolm/6842483804/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/6842483804/" title="Flying seagull 2 (uncropped original)"><img src="http://farm8.staticflickr.com/7050/6842483804_ac0d5b42c8_m.jpg" width="240" height="160" alt="Flying seagull 2 (uncropped original)" /></a></p> <p>This is an example of the kind of thing that's very difficult to photograph with a 500mm lens. Unless you've fitted it with some kind of sighting aid. This was taken <a href="http://www.flickr.com/photos/chris_malcolm/6988604369/">with the aid of a red dot gun sight fitted to the lens barrel</a>. I was catching such shots almost every time a gull flew past, whereas without it I'd manage to catch maybe one in twenty. <br /> <br /> Apart from that technical interest it's a crap photo taken on a seriously overcast misty day. I include this unprocessed image to show what it looked like in the finder. <a href="http://www.flickr.com/photos/chris_malcolm/6988606525/">It crops down and polishes up fairly well</a>, but of course not a patch on what could have been done with better light.<br /> <br /> <br /> DSC05996X</p> Fri, 16 Mar 2012 18:03:35 -0700 2012-03-15T11:38:05-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/6842483804 Flying seagull 2 (uncropped original) <p>This is an example of the kind of thing that's very difficult to photograph with a 500mm lens. Unless you've fitted it with some kind of sighting aid. This was taken <a href="http://www.flickr.com/photos/chris_malcolm/6988604369/">with the aid of a red dot gun sight fitted to the lens barrel</a>. I was catching such shots almost every time a gull flew past, whereas without it I'd manage to catch maybe one in twenty. <br /> <br /> Apart from that technical interest it's a crap photo taken on a seriously overcast misty day. I include this unprocessed image to show what it looked like in the finder. <a href="http://www.flickr.com/photos/chris_malcolm/6988606525/">It crops down and polishes up fairly well</a>, but of course not a patch on what could have been done with better light.<br /> <br /> <br /> DSC05996X</p> Chris_Malcolm birds misty reflex overcast 500mm bif reddot http://www.flickr.com/photos/chris_malcolm/6988607441/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/6988607441/" title="Flying seagull 1 (uncropped original)"><img src="http://farm8.staticflickr.com/7039/6988607441_a9d11c2b45_m.jpg" width="240" height="160" alt="Flying seagull 1 (uncropped original)" /></a></p> <p>This is an example of the kind of thing that's very difficult to photograph with a 500mm lens. Unless you've fitted it with some kind of sighting aid. This was taken <a href="http://www.flickr.com/photos/chris_malcolm/6988604369/">with the aid of a red dot gun sight fitted to the lens barrel</a>. I was catching such shots almost every time a gull flew past, whereas without it I'd manage to catch maybe one in twenty. <br /> <br /> Apart from that technical interest it's a crap photo taken on a seriously overcast misty day. I include this unprocessed image to show what it looked like in the finder. <a href="http://www.flickr.com/photos/chris_malcolm/6842485040/">It crops down and polishes up fairly well</a>, but of course not a patch on what could have been done with better light.<br /> <br /> <br /> DSC05997X</p> Fri, 16 Mar 2012 18:04:15 -0700 2012-03-15T11:38:22-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/6988607441 Flying seagull 1 (uncropped original) <p>This is an example of the kind of thing that's very difficult to photograph with a 500mm lens. Unless you've fitted it with some kind of sighting aid. This was taken <a href="http://www.flickr.com/photos/chris_malcolm/6988604369/">with the aid of a red dot gun sight fitted to the lens barrel</a>. I was catching such shots almost every time a gull flew past, whereas without it I'd manage to catch maybe one in twenty. <br /> <br /> Apart from that technical interest it's a crap photo taken on a seriously overcast misty day. I include this unprocessed image to show what it looked like in the finder. <a href="http://www.flickr.com/photos/chris_malcolm/6842485040/">It crops down and polishes up fairly well</a>, but of course not a patch on what could have been done with better light.<br /> <br /> <br /> DSC05997X</p> Chris_Malcolm birds misty reflex overcast 500mm bif reddot http://www.flickr.com/photos/chris_malcolm/6988606525/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/6988606525/" title="Flying seagull 2 (processed)"><img src="http://farm8.staticflickr.com/7056/6988606525_aa49d4c6cd_m.jpg" width="240" height="153" alt="Flying seagull 2 (processed)" /></a></p> <p>This is an example of the kind of thing that's very difficult to photograph with a 500mm lens. Unless you've fitted it with some kind of sighting aid. This was taken <a href="http://www.flickr.com/photos/chris_malcolm/6988604369/">with the aid of a red dot gun sight fitted to the lens barrel</a>. I was catching such shots almost every time a gull flew past, whereas without it I'd manage to catch maybe one in twenty. <br /> <br /> Apart from that technical interest it's a crap photo taken on a seriously overcast misty day. This is a cropped down and polished image (probably over polished).<br /> <br /> <a href="http://www.flickr.com/photos/chris_malcolm/6842483804/">This links to the original unprocessed image</a>.<br /> <br /> <br /> DSC05996RW_ntX</p> Fri, 16 Mar 2012 18:03:40 -0700 2012-03-15T11:38:05-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/6988606525 Flying seagull 2 (processed) <p>This is an example of the kind of thing that's very difficult to photograph with a 500mm lens. Unless you've fitted it with some kind of sighting aid. This was taken <a href="http://www.flickr.com/photos/chris_malcolm/6988604369/">with the aid of a red dot gun sight fitted to the lens barrel</a>. I was catching such shots almost every time a gull flew past, whereas without it I'd manage to catch maybe one in twenty. <br /> <br /> Apart from that technical interest it's a crap photo taken on a seriously overcast misty day. This is a cropped down and polished image (probably over polished).<br /> <br /> <a href="http://www.flickr.com/photos/chris_malcolm/6842483804/">This links to the original unprocessed image</a>.<br /> <br /> <br /> DSC05996RW_ntX</p> Chris_Malcolm birds misty reflex overcast 500mm bif reddot http://www.flickr.com/photos/chris_malcolm/6842482066/ <p><a href="http://www.flickr.com/people/chris_malcolm/">Chris_Malcolm</a> posted a photo:</p> <p><a href="http://www.flickr.com/photos/chris_malcolm/6842482066/" title="500mm reflex with red dot sight (front)"><img src="http://farm8.staticflickr.com/7054/6842482066_16b44069d5_m.jpg" width="160" height="240" alt="500mm reflex with red dot sight (front)" /></a></p> <p>500mm lenses are difficult things to aim, especially when the thing you're trying to find is against a featureless background, and almost impossible if the thing is moving fast, such as a bird in flight. Like a big telescope they need some kind of sighting aid. A red dot gun sight with no magnification is very good, because it allows you to look with both eyes open and see a red dot projected on your target (an optical illusion, not a laser beam :-).<br /> <br /> They're designed to clamp onto a gun sight wedge mount, so some kind of adapter is required. I played with the hot shoe mount, but it was too flexible -- the sight needed re-zeroing at every mount, and was easily knocked out of calibration. The degree of precision required to aim the central focus sensor at the target via the dot also made parallax error a problem on the hot shoe. So I decided to mount it directly on the lens. Least parallax error, plus the geometry of the lens barrel and the sight mount naturally lines it up with the lens. To protect the lens barrel I glued the sight clamp to a cardboard tube slightly too small, slit open to provide a sprung grab on the lens body. The slit also handily accommodates the focus hold button on the lens barrel.<br /> <br /> It works amazingly well! It's now trivially easy to aim the lens at anything very quickly indeed, including birds in flight. Getting the lens to lock focus on a bird is a bit trickier. Without bothering to zero the sight carefully I found that If the flying bird occupies at least 1/10th of the image the AF manages to lock focus quite soon. But tiny birds, or distant birds, often fail to lock just using the red dot sight, and if you drop to viewfinder or live view the view becomes so narrow the bird is easily lost. So experiments with careful calibration and technique are required.<br /> <br /> But initial results are very encouraging! This has suddenly become a VERY much more useful and easily used lens! Although having a gun sight on top of it does reduce one of the advantages of a 500mm reflex lens -- it doesn't look like a long lens, so people are less nervous of it than a foot long lens with a dinner plate objective.<br /> <br /> <br /> DSC05978X</p> Fri, 16 Mar 2012 18:02:25 -0700 2012-03-15T00:18:50-08:00 nobody@flickr.com (Chris_Malcolm) tag:flickr.com,2004:/photo/6842482066 500mm reflex with red dot sight (front) <p>500mm lenses are difficult things to aim, especially when the thing you're trying to find is against a featureless background, and almost impossible if the thing is moving fast, such as a bird in flight. Like a big telescope they need some kind of sighting aid. A red dot gun sight with no magnification is very good, because it allows you to look with both eyes open and see a red dot projected on your target (an optical illusion, not a laser beam :-).<br /> <br /> They're designed to clamp onto a gun sight wedge mount, so some kind of adapter is required. I played with the hot shoe mount, but it was too flexible -- the sight needed re-zeroing at every mount, and was easily knocked out of calibration. The degree of precision required to aim the central focus sensor at the target via the dot also made parallax error a problem on the hot shoe. So I decided to mount it directly on the lens. Least parallax error, plus the geometry of the lens barrel and the sight mount naturally lines it up with the lens. To protect the lens barrel I glued the sight clamp to a cardboard tube slightly too small, slit open to provide a sprung grab on the lens body. The slit also handily accommodates the focus hold button on the lens barrel.<br /> <br /> It works amazingly well! It's now trivially easy to aim the lens at anything very quickly indeed, including birds in flight. Getting the lens to lock focus on a bird is a bit trickier. Without bothering to zero the sight carefully I found that If the flying bird occupies at least 1/10th of the image the AF manages to lock focus quite soon. But tiny birds, or distant birds, often fail to lock just using the red dot sight, and if you drop to viewfinder or live view the view becomes so narrow the bird is easily lost. So experiments with careful calibration and technique are required.<br /> <br /> But initial results are very encouraging! This has suddenly become a VERY much more useful and easily used lens! Although having a gun sight on top of it does reduce one of the advantages of a 500mm reflex lens -- it doesn't look like a long lens, so people are less nervous of it than a foot long lens with a dinner plate objective.<br /> <br /> <br /> DSC05978X</p> Chris_Malcolm diy reflex 500mm reddot