Adapter for lens to use as a telescope

<p>I saw an adapter a friend of a friend had a few years ago that mounted on the back of a standard SLR lens that together turned the lens into a telescope. Do anyone know of such an adapter for Canon EF mount lenses? Is this a good idea? Does it work well?</p>

<p>Chuck, are you referring to an eyepiece adapter that mounts behine a camera lens? I've seen those on that auction site but rather infrequently, so I don't think it's a standard part that's manufactured today.</p>

<p>In general, I would say that you'd probably be better off buying a dedicated telescope. Modern refractors are quite decent and inexpensive for casual viewing, also a lot cheaper than an equivalent camera lens of the same focal length.<br>

<<a href="http://www.google.ca/#hl=en&q=refractor+telescope&aq=3&aqi=g10&aql=&oq=+refractor&gs_rfai=&fp=445cfd656cc6af0d">Link</a>></p>

<p>I don't know of any that work directly on a Canon EOS lens mount. Mostly they were made and marketed either for T-mount lenses (like the many 500mm mirror lenses of now and then), and a few were made for M42x1 mount lenses.</p>

<p>Any telescope adapter, to be useful, has to have erecting optics of some sort, or the image will be upside down, of course.</p>

<p>Here is a Soviet-made M42x1 one called (in Cyrillic) the Turist-FL. The Spiratone company sold a telescope adapter in T-mount. A few versions were quite short, compared to these two. I got the Soviet one from a military salvage outfit, but I think they sold all they had. eBay is your friend if you still want one. I always wanted one, but like the slide-duplication device, it sounds more useful than it is.... :p</p><div></div>

<p>These used to be available from places like Spiratone and Cambridge (the old Cambridge) and the like. I have one for the Nikon F mount, and a friend of mine had one for Minolta. It's not a bad way to add a scope to your kit if you're carrying a longish lens anyway, or if you have a spare one that you don't need for anything else, but the results are not as good as you'd get from a halfway decent spotting scope. I used to use mine for a while on an old 70-260 Soligor zoom that had a nasty bit of chromatic aberration after a bad drop, and it's a pretty useful way to get life out of a lens whose photographic life is over. </p>

<p>A little too late for just an edit, but I might have to modify my response a little, because I just tried mine out after a long hiatus, and it's really not that bad. What I have is a "Spectralstar" adapter, which is quite short, with some optics in it. This one gives about a 25x scope from a 200 mm. lens, with reasonable clarity and brightness, depending of course on the lens itself, and also pretty good near focusing.</p>

<p>If you can get one cheaply enough, this could well be a good use for a clunky old zoom that has no home on a camera any more. Here it is mounted to my old T-4/Nikon mount Soligor. I think I originally got the adapter by mail order back in the 80's, but it could also have been from a Ritz store or something of the sort.</p>

<p>Remember though that you'll get poor results unless the lens has a tripod mount of its own. It's not easy to hand hold a scope of that magnification. I should also mention that for reasons unknown this adapter never worked on an old T2-/Nikon mount mirror lens I have. It just wouldn't focus even though the lens worked well enough on a camera.</p><div></div>

<p>Perhaps you saw the Nikon Lens Scope Converter? It attaches directly to Nikkor F mount lenses and gives erect viewing with a magnification of 1X for every 10 mm of primary lens. I occasionally attach mine to one of my long lenses and tripod mount it. e,g, I get a 50X image with my 500 f/4, and 70X when a 1.4 X TC is added. It is not easily used for astronomical viewing though, as it is a bit front heavy without the weight of a camera body, making it a problem in following the drift across the field. However it is fine for terrestrial viewing, with very sharp images and an apparent field angle of about 60 degrees. I wonder if there is a Canon to Nikon adapter which would allow fitting a Canon lens to it?</p>

<p>What are you looking at? I see people using these spotting scopes which already have an erecting prism designed to work with the scope. Check out the products by <em>Leupold</em> for one. Then go look at wolves and grizzlies and wrens and little night critters. No, I doubt it is a good idea. Using a spotting scope the other way, with a <em>Nikon </em>point and shoot is a whole other story. Sorry, that exhausts my little knowledge in response to your specific query, wish I knew more. To appraise what is out there, try to look at <em>Orion</em> telescope for a wide range of optics that are less costly than Nikon's offerings.<br>

Me, I just love the two eyed view from lowly binoculars, like in the 150-200 buck range like those from Pentax a good outfit for such stuff. Two eyes is nice for seeing stuff long distance especially in dusk and night. aloha, gs</p>

<p>Alex, I'd forgotten that Nikon made a proper version of the gadget I have. In case it wasn't clear in my previous post, mine is a Nikon mount adapter, not a T, and I know these third party ones were made for some other mounts, but I don't know whether they survived into the EOS era.</p>

<p>A little googling suggests that there is no such accessory available, but that people have found various ways of doing it. Here's one page: </p>

<p>http://www.iscap.columbia.edu/jank/Photo/Info/Eyepiece_Adapter/index.html</p>

<p>Note that this setup leaves you with an inverted image. The Nikon adapter Alex has, and its imitators like the Spectralstar, had a prism inside to give an erect image.</p>

<p>Oh wait! I should have known, all you need to do is go to Photo.net! Here it is in the Nikon forum, but clearly applicable to other lenses, how to make an erecting eyepiece converter using a rear lens cap:</p>

<p>http://www.photo.net/nikon-camera-forum/00HfRR</p>

Some of these adapters have poor eye relief and narrow fields of view so if possible try before you buy.

<p>Or you could get a T mount attached to this <a href="http://www.adorama.com/Als/ProductPage/BS780104.html?sid=12723427235282">http://www.adorama.com/Als/ProductPage/BS780104.html?sid=12723427235282</a></p>