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Ulophot
10-Aug-2020, 06:13
The recent thread on front/back tilt led me to discover that the Copal 1 in which my 210mm is mounted does not get all the way to f/45 but stops about 2/3 of the way between f/32 and the f/45. I'm quite sure it used to go just slightly past 45. I had it serviced about two years ago and haven't used it more than monthly since. What causes this? I guess I'll have to send it out for service again.

Thanks.

Bob Salomon
10-Aug-2020, 07:22
Do you have the correct aperture scales for your lenses?

Luis-F-S
10-Aug-2020, 18:35
My 8 1/4” Dagor easily goes past f/64 to close to f/90! Mounted in the Copal 1 by SKG.

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Ulophot
10-Aug-2020, 18:48
Bob, the lens was bought from a leading large format specialist in NYC, who mounted it in the shutter about 40 years ago. I have no reason to doubt that the scale is correct.

Bob Salomon
10-Aug-2020, 19:20
Bob, the lens was bought from a leading large format specialist in NYC, who mounted it in the shutter about 40 years ago. I have no reason to doubt that the scale is correct.

If it was remounted into a shutter it can easily have the wrong scales. Contact Rodenstock Service and ask them the code number on the scale for your lens.

Ulophot
11-Aug-2020, 06:01
Will do.

Ulophot
11-Aug-2020, 14:21
Solution discovered!

Well, live and learn -- and in this case, at least my memory was correct!

I had sent a message to Rodenstock this morning, but something was not right. I have used this lens with films from chromes to B&W with accurate exposure results since its purchase c. 1978.
Wondering if I could see anything else on the shutter that might be causing the problem, I removed the mounted lens from my bag and found -- mirabile dictu --that there is nothing at all preventing its full travel well past f/45, probably f/64! Delighted and perplexed, I mounted the lens on my camera (Tachihara 4x5 field), where once again the aperture stopped short. Close examination showed that the auxiliary piece that travels ahead of the aperture indicator (I guess it's a pointer for cylinder-side scales) was hitting the metal piece that holds the Technika board to the camera. This is so, because the lens is mounted off-center, low on the board.

If I turn the lens a bit, all will be well.

What a relief! Except for what it says about my eyesight...

Luis-F-S
11-Aug-2020, 18:24
I remembered I have other 210 lenses, so I pulled out a 210 G Claron f/9 and a 210 Caltar II f/6.8 Here's the shot below with the caltar on left. The Caltar goes well past f/64 close to f/90 and the G Claron is marked up to f/90. Glad you solved your dilemma.

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