M42 screw lens types

[ariel7515]

Hello!

Just wanted to ask you about the different types of M42 screw lenses, the case here is a Carl Zeiss Jena Tessar 50 mm f/2.8 (middle of the 50s), it came with a Praktica FX camera, an excellent lens but I'm having problems to use it with a C/Y adapter. I do not know exactly how to explain it in English, but the back of the lens is longer (from the screw to the rear end) than in a modern M42 lens, e.g. a Super-Takumar 50mm f/1.8, so when I try to screw it in the adapter, the rear part reaches the base/end of the adapter before completion, and that difference in the flange focal distance makes impossible to focus to infinity.

Do you know is called such lens type and if there is any adapter for it?

Thanks!

 

[excalibur2]

Well I'm not sure what the problem is as my Tessar fits the C\Y adapter and works perfectly on a Contax 139, maybe it doesn't work properly on a Yashica camera (haven't got one anymore). Also the Tessar screws in about the same distance as a Tak....without looking it up maybe there are different types of CJ Tessars and they changed over the years.
Mind you one screw lens I have will not screw into my old screw Pentax, but does on an old Praktica so all screw lenses are not the same.

 

[ariel7515]

1954 Carl Zeiss Jena Tessar 50mm ƒ/2.8 red T Alu preset 1Q by .: mike | MKvip Beauty :., on Flickr

OK, now check the Tessar, the conical black part right after the screw and now compare it with the Takumar... see?... that extra section is the issue, but not only with the C/Y adapter, if I screw the Tessar to a M42 body like with my Cosina Hi-Lite EC, the extra section push back the stop-down lever (the one that pushes the pin in auto lenses like the Takumar) making it useless. I'm using a Takumar to compare but you can do it with any modern M42 lens.

 

[stevelmx5]

What happens if you remove the two screws in the back of the lens? Looks like they're holding the extra section on.

 

[excalibur2]

Ah mine's the newer CZJ Tessar and similar to the Tak...The worst M42 lens I have for verstality is the Helios 58mm f2 as it won't screw fully home on an old Pentax camera or using the C\Y adapter on a Contax..but a surprise as it screws in properly in a Chinin CE m42 memotron camera.

 

[abdoujaparov]

Do you have an expensive (Metabones/Fotodiox, etc) or cheap adapter? I'm wondering if the adapter is only designed for auto lenses and not preset ones.

 

[ariel7515]

What happens if you remove the two screws in the back of the lens? Looks like they're holding the extra section on.

I will never know... I will not dare to tamper with a 60 years old fully working lens , if I can find an adapter, ok, if not I will use it with the Praktica FX body and that's it.

Anyway, I would like to know about why that difference in the construction, maybe it was some kind of standard back in the day and affects other lenses than just the CZ.

Ah mine's the newer CZJ Tessar and similar to the Tak...The worst M42 lens I have for verstality is the Helios 58mm f2 as it won't screw fully home on an old Pentax camera or using the C\Y adapter on a Contax..but a surprise as it screws in properly in a Chinin CE m42 memotron camera.

I've tried a Helios 44 on a Zenit E body and on a Canon DSLR using the adapter, on both without any problems, lucky for you if you have a nice camera body to use it.

Do you have an expensive (Metabones/Fotodiox, etc) or cheap adapter? I'm wondering if the adapter is only designed for auto lenses and not preset ones.

I have the cheap one but it is the same as the fotodiox:

http://www.bhphotovideo.com/c/product/774450-REG/Dot_Line_DL_0621_Lens_Mount_Adapter_M42.html

 

[Sejanus Aelianus]

I can't find the reference at the moment but I think the FX series had a smaller mirror than later cameras, so the rear element of lenses designed for those cameras could be further back. Later bodies had bigger mirrors for use with longer focus lenses without cut-off, so the rear elements had to be redesigned to accomodate this. The reverse happened with Canon's dSLRs, when they introduced lenses specifically for the APS format that would fit onto a full frame camera but foul the mirror.

 

[excalibur2]

I



I've tried a Helios 44 on a Zenit E body and on a Canon DSLR using the adapter, on both without any problems, lucky for you if you have a nice camera body to use it.

It would interesting to know if your Tessar would fit the later Praktica cameras...but looking at the pic my guess would be that it wouldn't.

 

[ariel7515]

I can't find the reference at the moment but I think the FX series had a smaller mirror than later cameras, so the rear element of lenses designed for those cameras could be further back. Later bodies had bigger mirrors for use with longer focus lenses without cut-off, so the rear elements had to be redesigned to accomodate this. The reverse happened with Canon's dSLRs, when they introduced lenses specifically for the APS format that would fit onto a full frame camera but foul the mirror.

Yes, it makes a lot of sense, I did not think about that, thanks.

Do you know if there is an adapter available for those kind of lens?, in the case of Yashica bodies, that extra space will not affect any lever or touch the mirror, the only option I can think of is to cut off the base of my current adapter, that way the lens will fit as it should.

It would interesting to know if your Tessar would fit the later Praktica cameras...but looking at the pic my guess would be that it wouldn't.

A very interesting test, but I do not have any other Praktica than the FX or M42 body.

 

[excalibur2]

Well Ariel I with you on the added hobby of playing with lenses, but it seems a lot of faffing around just to use your Tessar on a Yashica camera, and although the Tessar is a sharp lens......what is special in the results for your lens as there are plenty of alternatives just as good (and IMO better) that you could use.

 

[ariel7515]

Well Ariel I with you on the added hobby of playing with lenses, but it seems a lot of faffing around just to use your Tessar on a Yashica camera, and although the Tessar is a sharp lens......what is special in the results for your lens as there are plenty of alternatives just as good (and IMO better) that you could use.

Yes, it is true, but I was hoping to find some cheap adapter for that kind of old lens, just as an excuse to use it more often.

 

[excalibur2]

Yes, it is true, but I was hoping to find some cheap adapter for that kind of old lens, just as an excuse to use it more often.

Well I wouldn't think the Chinese would make a special C\Y adapter for a film camera as it's cheaper to copy the original metal one that was made at the time...and sell that to more buyers.