Camera question re lenses

[Murphyv310]

Hi.
Perhaps not in the correct section, so mods if wrong please delete or move to the best section.
Simple question, I'd like to use dads Zorki telephoto lens on either the Pye Lynx or a Sony B/W 625 line camera, both have the same thread. Is there such a thing as thread adaptor? The Zorki has a Leica thread but I'm not sure of the type the TV cameras use.
Any idea folks?

[ppppenguin]

Industrial TV cameras of that period use C mount lenses. I've certainly seen adaptors for using larger diamter lenses on C mount cameras. Google C mount adaptors and you should find something.

https://en.wikipedia.org/wiki/C_mount

[Murphyv310]

Cheers Jeffrey, I was told a few years ago what mount it was but it had been erased from my brain.
Will have a look on eBay today.

[ppppenguin]

All sorts at a price here: https://www.edmundoptics.co.uk/microscop...s/?site=UK&countryid=231

Make sure you get an adaptor that's the right way round. C male to [your other] female. For reasons I don't understand you seem to be able to get them for fitting C mount lenses to cameras that take larger ones. Surely this would give severe vignette effects.

Another possible problem is the back focus distance. Since larger diameter lenses typically have longer back focus distance you are probably OK.

Make sure it's mechanically secure too. A big long lens hanging off a small C mount may need an extra support.

[Murphyv310]

Thanks Jeffrey.
I did try the Jupiter 11 (Zorki telephoto) lens with a bit of a lash up last year and the result was excellent with good focus from 2 meters up to infinity. These Soviet lenses are very high quality and it gave very good results on the Lynx and Sony camera.
I've done all the mods to the Lynx circuitry and its now got proper locked timebases so I'd like to do some video stuff on 405 as an experiment, do need the addition of telephoto though. The Zorki (Jupiter) lenses are rangefinder types with the old Leica thread.

[ppppenguin]

I think the old Leica thread is also known as Leica Thread Mount and also as M39. This may help your search.

https://en.wikipedia.org/wiki/M39_lens_mount

[beamcurrent]

Jeffery has covered most of the mounting details but I feel I ought to mention the image size. A statement of the obvious perhaps but the 35mm lens is meant to work with 35mm film stock.

The vidicon tube has an image "patch" that approximates to 16mm film so the tube will only be using the center portion of the 35mm lenses "patch" size. The lens will appear to have a longer focal length and be less sensitive due to the loss of light in the unused portion of the 35mm patch.

An additional lens could be used if one can be found to change the patch size or the rear element of the exiting lens could be changed. Both these options are difficult and probably not worth the bother.

regards

Brian

[Old Sparky]

I hav for many years owned a Zorki 4K, with 35, 50, & Jupiter 11, 135mm lenses and the accessory viewfinder, so have been reading the information pages* with interest. Haven't used the camera for several years, but have never had to carry out any adjustments to it. I've no idea whether the lenses would be compatible with 625 line cameras, though! * I googled FED Cameras, and found, among other things, full details of how to service & adjust these cameras, but don't remember the link to the site in question!

[Murphyv310]

I'd agree with the image patch and that it could make the camera seem less sensitive.
Using the standard Jupiter 8 lens on a lash up last year it did give the impression I was using a small telephoto lens, not a problem as that was my intention. When I tried the 135 Jupiter 11 the results were still excellent.