Not that sort of shooting, but with a camera and long lens. One of the ongoing frustrations of photographing small and/or distant subjects with a long telephoto lens, is that it can be very difficult to keep track of the subject if it’s moving about. I often find this happening when photographing smaller birds or birds in flight, as evidenced recently when trying to photograph some eagles high in the sky. Peering through the camera viewfinder with a very long focal length lens, especially hand held, means that you’re constantly losing track of erratically moving birds, as the field of view in the viewfinder is very narrow and this often leads to many missed shots. Just to refresh, these two were awfully difficult to follow with a long lens.
So what’s a photographer to do under these circumstances? As it happens, there’s actually a reasonably easy and cheap solution to this problem, do what rifle shooters have been doing for some time now and use a wide field rifle sight. These sights are commonly referred to as red dot/green dot, reflex or holographic, sights and allow you to sight the target with both eye’s open and see everything in front of you at the same time. They come in a number of styles and, as with just about everything, you can get these very cheaply from eBay. It doesn’t mean that the cheap ones will be of exceptional quality, but for photographic use where the accuracy that’s needed for rifle shooting isn’t required, they should prove more than adequate. The main issues are whether the sight has sufficient adjustment to accommodate a large lens vs a rifle barrel and how easily it can be adapted to a camera.
And as things would have it, as soon as I went out and bought a dot sight, one is announced by a camera manufacturer specifically for use on a camera. This sight is also a folding one, so it should be very easy and safe to carry around. If my cheap dot sight doesn’t perform quite as expected, then I have a fallback with this camera dedicated unit, which may be a better option in the long run regardless.
Because my intent was to set this sight on the lens for hand holding, making a suitable mount wasn’t all that difficult. My only concern was whether there would be sufficient adjustment available on the sight, considering that I was using it for other than its intended purpose. The adjustment is necessary so that when the lens is centred on a subject, the sight is centred on the same spot. Once the mount was constructed, the alignment process was actually quite easy and there was more than enough adjustment available. All that was required was to select live view on the camera, point the lens at a distant subject and press the shutter button to confirm the focus point; then the sight was adjusted until the dot was centred at exactly the same point as the lens. It took several attempts and photographs to get it right, but in the end it was close enough.
Now the adjustment is only good for the lens at full zoom, else you need to readjust the sight if you want any other zoom focal length; but as it was my intention to use this sight only at full focal length, it doesn’t really matter. However, after carrying out some tests hand-holding the lens, I discovered that the sight was simply too far away and located too high up from the camera for comfortable use. So it was back to the drawing board with a new idea for the mount, which was going on the hot shoe. After a bit of digging in my parts bin and some workshop adjustments, I had a new mount.
Once again I had to go through the sight adjustment process, but this time, as I could now use a tripod, the adjustment process was a lot easier. While the sight still sits higher than I’d like, it’s quite effective and comfortable to use. How much better the factory sight would be is anyone’s guess at this time, and given more time and inclination, I could further modify the mount so that it’s an even better fit. Afterall, this was mainly a trial and there’s still testing to be done.
One thing that’s certainly evident is that there’s a lot of small movement that will affect the accuracy of the mount when it’s on the hot shoe. Firstly, the camera turns ever so slightly on the lens mount, so that will throw off the accuracy of the sight. Secondly, the sight moves about on the hot shoe mount, so that also throws off the accuracy. What needs to be done each time the sight is used, is to run some tests to ensure that the sight is centred, with all movement settled, to ensure the accuracy of the sight. In this respect, the lens foot mount is still the better proposition, as it does not move once locked in place. I’m not finished yet, so stay tuned.
Oh yes, always remember to turn off the sight!
Update 1. Well, that didn’t take long. I wasn’t happy at all with the last mount, as it added extra weight to the sight and likely contributed to the movement, so I went back to the drawing board and started afresh. This time I made a dovetail plate to fit the 11mm Weaver mount and attached the hot shoe foot to the end. The entire assembly is now about 50% lighter, so less weight on the hot shoe and I can fit it very firmly on the hot shoe so that there’s no movement. A quick re-alignment and some further test shots confirms that this is much better.
Update 2. Despite being a firmer fit, there was still too much movement in mount Mk III, so once again I went back to the drawing board and started anew. The little hot shoe adapters that I’d bought from eBay were great for things like my portable LED light, but no where near precisely made and positive enough for a dot sight. This time I made a completely new foot (by happenstance I had just the thing for this – never throw anything away) and after about half an hour of methodical grinding and filing, I had a perfect fit for the hot shoe. This time is was a firm fit, as after putting it on and taking it off a number of times, it remained firm, unlike Mk III.
Additionally, after aligning the dot mount to the main lens once again, I tried it out with my other lenses and, surprisingly, it was equally aligned with those. So it appears that it wasn’t the dot sight, but the inadequacy of the earlier mounts that affected it’s performance with other lenses. I might add that zooming with the long lens won’t work, as then the sight will be out of alignment. And as things will have it, now that the sight is ready for use, not a bird has been in sight anywhere; I hope that an Autumn Diaspora doesn’t mean I’ll need to wait until next Spring to make full use of this sight.
Update 3. I still wasn’t entirely satisfied with the setup, so I did some further modifications to lower the profile of the sight and remove the need for the lock screw. This ended up being easier than I thought and the sight now sits firmly on the hot shoe, yet is easy to remove and install. A much better solution all round.