ZM-5A 500mm Lens Mounting?

[Macklin]

This is my first post on this forum and so far it seems pretty cool.

I'm not a photographer, nor do I know much about photography or lenses in general - so bare with me. The other day I bought a Russian ZM-5A (3M-5A) 500mm lens from an op-shop for a ridiculously cheap price (it looked like the coolest thing ever. I had to take it home with me) and since then I've wanted to know anything and everything about it. It differed to the other ZM-5A's that I've seen online, instead of having a T-mount + M42 adapter used for photography it had a prism-like telescopic attachment which allowed it to be used as a astronomical telescope. This prism attached to the lens by sliding into a groove and was secured to the body with 3 flat screws.

Curious to see if I could use it with an SLR, but baffled by how I would attach it - I emailed the guys at telescope-service. They gave me some information about back focus and some other stuff I didn't understand and told me that I would need a custom-made attachment in order for the lens to be used for things other than the prism.

So it seems I need something that attaches to the lens the same way that the prism does (can be slid on and secured with 3 flat screws), offering some sort of standard camera adaption on the other end (preferably so that it can be usable with an EOS 30d [EF-mount]). I've searched online, but I'm not sure what I'm looking for exactly and if it would fit the lens, but I mostly found adapters that would attach to a mount that would be in place of the prism (I think).

I've probably done a horrible job trying to explain - so heres some photos.
1 - http://forum.mflenses.com/userpix/20122/5249_IMG_0062_1.jpg
2 - http://forum.mflenses.com/userpix/20122/5249_IMG_0063_1.jpg
3 - http://forum.mflenses.com/userpix/20122/5249_IMG_0064_1.jpg
4 - http://forum.mflenses.com/userpix/20122/5249_IMG_0065edt_1.jpg (w/o prism)
5 - http://forum.mflenses.com/userpix/20122/5249_IMG_0067_1.jpg (w/o prism)
i.e. where do I get one of these: http://www.ussrphoto.com/Wiki/Content/3703.jpg
If you need any more information, don't hesitate to ask.
Thanks!

[Fabian]

[Macklin]

^ Thanks =P, I have no idea...

[Attila]

Sharp lens , I have 500/f6.3 . Congrats! I think you need to make a custom adapter by qualified technician.

[flintlock1]

Hi Macklin,
This looks very similar to the problem that i had with my Russian MTO 1100a Mirror lens. The mount that i had to get was a Canon EF to T2 mount. I now have an M/42 T2 mount to use on it instead.
And i have the EF to T2 mount going spare. I could always swap you my mount for your Eye-piece thing if you want? PM me if you want.

[Macklin]

[M. Valdemar]

http://www.bhphotovideo.com/c/product/823961-REG/Bower_SLYTEL_10x_High_Power_Lens.html

Google "telephoto lens to telescope adapter". I bought one made in the 1960's by Spiratone for $7 on eBay. These used to be very common.

[Macklin]

I don't think it's an adapter that I'm looking for - just some sort of part that can be attached to the lens in the same way that the prism does. Attila might be right, but I'm hoping that getting a custom fitting isn't the only option.

[fuzzywuzzy]

[Macklin]

[Macklin]

I may have figured out my problem, but I'm not 100% sure that it'll work or not. After some trawling in the depths of the Internet, I've found out that the ZM-5A originally had a T-mount with an M42 adaption. When I looked at the T-mount adapters that were available on eBay and Amazon most seemed to have a screw thread on the inside of the ring, even though they had the 3 set screw holes visible on the outside - something that at first I thought wasn't what I needed (my lens doesn't have any sort of threading).

Of course I had no idea at the time, I was actually looking at the T/T2 (or just called the T2) mount, which is the next version from the original T-mount. "The original T Mount slides onto a T mount lens. It is secured only by 3 set screws that match a channel on the lens mount so that the lens barrel is not deformed by the set screws, and it can be removed with no problem."

From this post: http://www.mu-43.com/f40/soligor-135mm-f3-5-what-mount-20768/ I found out that the T2 system is "a screw mount using a male M42x0.75 metric thread on the lens to attach the collar that the mount attaches to by the set screws". Originally I thought that they were two completely different adapters (idk, maybe because people still call it the T-mount instead of T2). But basically the T2 mount is just the addition of a threaded ring to the inside of a T-mount, and (presumably) is held in place by the 3 set screws.

I'm not sure (tell me if I'm wrong) but I think I can just remove the set screws and the inner ring so I'm left with just the outer part (the original T-mount), which I can then just attach to the lens as with my prism.

EDIT: I wrote this a while ago, and since then the adapter has arrived, but it seems to not fit snugly on the lens like the prism does. In fact, it isn't even the same width as the base on the lens. The adapter is approx 53mm at the T-mount end (without the T2 ring of course), the lens is about 49mm and the prism is about the same. Gah, this is frustrating! Maybe longer screws would do the job?

[aoleg]

No longer screws. Just buy another T2 adapter (different model, from another seller etc.) and try agian. They're all slightly different; one fits, another doesn't. If you can't find one, PM me and I might have the right adapter for you. By the way, they were called "A" mount in Russian photo literature. Same thing as used by Jupiter-37A, Tair-11A, Mir-10A and a few other "A" lenses with an "A" at the end of the model number. Just like your 3M-5A lens

[Macklin]