aus jena ddr 50 f 2.8

alireza1200 · Joined: 12 Mar 2019 Posts: 2

hello guys sorry for my bad English i am not native any way!

i got a copy of this lens aus Jena ddr 50 f 2.8 it made bay estarn Germany and its structure i guess is different from carrel ziss jena 50 f 2.8. i dissemble it because there is a problem with aperture blade it actually got stuck and doesn't work fine
my main problem is with the front part it seems different with carel ziss and it is one piece ( carle ziss one has a name ring and after screw it you can see 3 pin but this one seems doesn't)
if i want to reach aperture blade i have to open this part. is there any one who have any idea or any experience about my problem.

this picture belongs to the front part

https://8pic.ir/uploads/3_07aa6.jpg

https://8pic.ir/uploads/1_d924e.jpg

i am glad to see your opinion.
thanks in advance.

mareinke · Joined: 14 Nov 2013 Posts: 33 Location: LA, CA

Hi alireza1200,
Apply several drops of acetone, sometimes lighter fluid also works
Heat up the name ring with a hair dryer

Marco

alireza1200 · Joined: 12 Mar 2019 Posts: 2

tanks a lot Marco your solution is fine but i don't know if this part is one peace or it opens from the front ring
for me it is amazing, anyway! i sent it for a friend of mine who are expert on repairing old lenses
i have to wait to know his idea. so i am trying to ask him how he fix it and release his answer here for any body who have the problem like me