CZJ Tessar 3.5/50mm with problem

uddhava · Expire: 2021-06-21

I recently purchased this Tessar lens along with the camera. It works fine except it does not reach infinity focus.
Is there any way to fix this problem?
Here is the camera and some photos. Click on images for larger size. Hope not too many. Embarassed

BTW, photos taken with Canon T3.

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This last one was shot at infinity.. after this everything gets blurry.
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Pancolart · Expire: 2013-11-18

Do not fix. You might loose this awesomeness. Very nice samples!

uddhava · Expire: 2021-06-21

PhantomLord · Joined: 08 Apr 2013 Posts: 472 Location: Szczecin, Poland

Well I could not figure out what possibly you could spoil when adjusting focusing ring to allow lens reach infinity.
I didn't do it on tessar, but just recently I adjust focusing ring on Pentax-M 50 1.7 and EBC Fujinon 55 1.8 and it actually took me about 20minutes per lens.

General idea is simple:
1. Take off front bezel with writings on it.
2. Locate and loosen screws that holds focusing ring to one of the helicoid's parts.
3. Turn the focusing ring from infinity sign, better do it in small steps.
4. Lock the screws that holds focusing ring.
5. Check if it is ok, if not, repeat from step 2. (I made about 3-4 adjustments per lens until I sett infinity spot on)
6. Put the front bezel in place (on Pentax it was easy to unscrew and put in place while using ruber bathtub plug, on Fujinon it was glued together with front ring and was easy to unscrew with 3 screws).

What I'm thinking you cannot spoil image results by doing so, only you put lens to it's proper working order. For both of my lenses it was worth it and it wasn't complicated.

Maybe some tessar users could put some more light into the topic as it your lens could have a little different constructional solutions. However, general idea of adjusting focus ring should be the same.

Nevertheless, nice photos, rich colours and sharpness, really like it.

Good luck

Aanything · Expire: 2014-05-30

Nice samples indeed.

For my little experience in opening them, jena lenses are not exactly straightforward in their build, so the risk of not being able to put it back together, if you're not an expert, is there.

It seems a really nice lens, and the good characteristics shown here should be more evident in medium to short range usage, so it may be ok to use it like that.

If infinity is not reached by little, you could also try and sacrifice an adapter, by sanding it down till you compensate for infinity - even if you mess this up you'll just have to throw away a cheap adapter.

philslizzy · Joined: 07 Aug 2012 Posts: 4745 Location: Cheshire, England

uddhava · Expire: 2021-06-21

Thanks for the tips everyone. I think I won't try to to fix the lens then. I am not so good at this type of thing any way. I do like this lens
very much as it is also.