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Stuart
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 16, 2004 - 11:25 am: | 
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Hi,
i am back, i got my IIIa up and running with some help from Mr. Oleson, and now am dealing with some lens issues.
Is there a standard distance that the focus cam protrudes from lens flange when the lens is focused at infinity? Or at any other point?
i ask because i now have two lenses, and they do not agree in this measurement. One (Schacht Travenar 135/3.5) is 8.1mm and the RF focus is way off, the other (Jupiter 8 50-2.0) is 7.5mm and is very good. I can reassembe the Schacht to 7.0mm protrusion, but i do not know if it is RF coupled correctly yet.
BTW if anyone has worked on the Schacht Travenar, please let me know. i have a question about the lens.
Thanks,
Stuart |
rick
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 16, 2004 - 07:25 pm: |
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I've measured the flange-to-cam distance on 8 different lenses. They range from 7.45 to 7.59mm. The best quality lenses (Leitz and Nikkor) are in the 7.55-7.59 range, so I've kind of settled on 7.55mm as the "correct" distance.
rick  = |
Stuart
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, April 17, 2004 - 12:36 am: |
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Thanks Rick,
i had a feeling you would answer.....
i kinda thought it would be a known, like the film to flange distance.
a hektor arrived in the mail today, it measures 7.56mm. it seems to be in good order, if a little worse for wear. i'll try to figure out how to get the schacht closer to 7.55mm |
Winfried
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, April 17, 2004 - 10:06 am: |
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I have two Schacht 135mm, one in the all chrome version (and with the early A.Schacht Muenchen engraving before they moved to Ulm in the early 50s) and a black one. The chrome one is a real pain to disassemble (it still rests on the shelf, reassembled but not adjusted yet). I did not work on the black one too much but I also had to readjust the coupling once. Let me know which version you have. |
Stuart
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, April 17, 2004 - 10:51 pm: |
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Winfried,
i have the chrome one from Muenchen. The rear element is easy, but i could not get to the front element. if i remember what i did was:
After removing the focus sleeve
Remove the infinity stop and three (well i have only one) grub screws
Unscrew the sleeve with the grips, this reveals one screw, remove that, then the aperture ring is loose. That is as far as i could get. i could not get the focus grip sleeve to come all the way off.
As there are flakes in the front elements i would like to remove, any help to get there would be greatly appreciated.
The coupling i have down pat. The infinity is now 7.42mm. i think that is as close as it will get.
Stuart |
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