Adapting / hacking Voigtlander Prominent 35mm

[spiffariffic]

I want to make a permanent mount for it. No adapter exists for this lens mount.

It has no internal focusing helicoid!

I free-lensed using an m42 adapter to provide 'structure,' BUT, the rear of the lens nestled quite deep into the tube.

A 17mm-31mm m42-m39 helicoid will take me from beyond infinity to quite close up.

So I figured that could be the basis for my hack.

But how to attach the lens to the helicoid?

It needs to be secure enough that I can turn the lens itself to turn the helicoid, since the grippy bit will be covered up by the lens' prominent wings.

I'm open to machining off the wings but don't have any idea how to go about that.

A complicating situation is that the back middle of the lens is spring-loaded. That is how the original camera attained focus on this lens, both by moving the shutter plane and pressing in the back element.

Hackers, help me out here!

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[kymarto]

I adapted the Prominent 50mm f1.5, which does not however have wings, by taping it with black pvc electrical tape to the helicoid. It is non destructive and holds well. It also stretches so it might work with your wings. The only other thing I know is to cannibalize a Prominent camera and take the mount, gluing it to a helicoid. I did this with an Aires V lens, which has a similar system. However I have never seen a Prominent camera and cannot guarantee it will work. On the Aires, after removing some screws, the mount actually comes out if you totally unscrew the helicoid. However a shame to destroy a working camera, unless you can find an old one that is totally trashed.

[Ultrapix]

I loved that lens in the film days, but I wouldn't struggle to adapt it to an aps sensor, it would mean to loose most of its magic IMHO. That said, I guess that any adapting made without some lathing work looks poorly promising to me

[Jozef_AV]

Why not print a custom piece that could connect the lens to your 17mm-31mm m42-m39 helicoid?
3D files for printing M42/M39 extension tubes that you could use as base are easy to find/download.
The lens attachment might be tricky but someone skilled could manage to design it to according to your description.

I used similar approach to mount some of my older projection lenses to my helicoids and it works "wunderbar"

J

[philslizzy]

dont touch the wings. Get a file to the adaptor and make the lens fit. Hold it on with a strip of black duct tape. Looks like a simple job to me.