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JimboWalker
25-Jun-2020, 17:14
I just purchased a 240mm Tele-Arton mounted in a NOS Copal No.1 shutter. CHEAP! How do I check that the lens elements are correctly mounted for optimal performance? I hope this lens does not need any adjustment. I'm curious about maybe any shimming or adjustment to mounting elements to shutter. Please, no snarky comments. Thanks!

BrianShaw
25-Jun-2020, 17:34
Take a picture. Use a tripod and focus carefully. Look at negative with loupe. If it as crisp as you’d expect for the aperture used... you’re good to go.

Dan Fromm
25-Jun-2020, 17:53
I just purchased a 240mm Tele-Arton mounted in a NOS Copal No.1 shutter. CHEAP! How do I check that the lens elements are correctly mounted for optimal performance? I hope this lens does not need any adjustment. I'm curious about maybe any shimming or adjustment to mounting elements to shutter. Please, no snarky comments. Thanks!

I don't mean to be snarky, but why are you so worried? If the lens fits the shutter at all it should be OK. If the cells are in artisanal home-made adapters, its risky. I'll bet they aren't. I have a couple of lenses whose cells are in home-made adapters. One set is clearly wrong, haven't tested the other 'cos I don't need the lens, which came to me as part of a bundle.

The 240/5.5 Tele-Arton was sold in two shutters. In Compur #1, recommended for 6x9, won't cover 4x5. In Compur II/5/2, recommended for 4x5. Cells that fit the II/5/2 won't fit the #1 without machining, the II's tubes have larger IDs. I don't know whether turning the cells down is possible.

Compur #1 and Copal #1 have the same tube lengths, IDs (front is larger than rear) and threading. No shimming should be needed when cells are switched from one to the other. In any case, you have neither the equipment nor the expertise to tell whether shimming is needed. No snark intended, if you had them you wouldn't have to ask.

At the worst you have a nice tele lens for 2x3. If you don't want to shoot 2x3, try it out to check that it works properly and resell it with an accurate description.

JimboWalker
25-Jun-2020, 18:17
Thanks to both of you so far! I am just anticipating what I do not know yet. I know I will just have to shoot it. I will be shooting a 6x7 back on my Pacemaker Graphic 4x5. Dan... You are correct. I have neither the equipment nor expertise.