are copal 0 shutters generic?

[norly]

Hoi.
A quick question. Are all Copal 0 standard shutters the same size? Are they directly interchangeable between different lenses?

Ive got one that gets stuck, and since I dont have time I figure I can take one from a backup lens and just replace it... From a Apo Sironar 150 , copal N 0.0 to a Schneider 72 XL.

The scales are the same.. and they look the same. But got different numbers.

Original was 10187A Copal 0 and the replacement would be 0011.065 Copal 0.

Thank you

[Dan Fromm]

Yes, but not quite. All shutters that conform to the Compur/Copal/Prontor #0 standard have the same tube length and threading. But and however, the #0 Copal Press shutter has a shorter rear tube, longer front tube than #0 cock-and-shoot shutters. This matters only for lenses whose rear cell goes deep into the rear tube. With them, the front of the rear cell may contact the diaphragm.

Scales are lens-specific. In particular, a scale for a longish lens probably won't be right for a shortish lens.

[norly]

Scales are lens-specific. In particular, a scale for a longish lens probably won't be right for a shortish lens.

Well if they have the same scale 5.6-45 they should be the same or? A aperture 5.6 is always a 5.6 no matter the lens right?

I also noticed that they had different thickness on the ring (loose spacer ring?) on the front element. But I moved it together with the lens, so it stays the same.

[sharktooth]

Well if they have the same scale 5.6-45 they should be the same or? A aperture 5.6 is always a 5.6 no matter the lens right?

Nope, the aperture is related to the focal length, diaphragm dia, and also the specific lens design. This means that f5.6 will require a larger diaphragm diameter with longer focal lengths, so the scale will be different for different focal lengths.

[norly]

Ah. Then I swap the scales as well. Thank you!

[xkaes]

I can't speak to all brands, but many Fujinon lenses have numbered aperture scales for the Copal shutters each lens is designed for. For example, the aperture scale for the NW 210mm f5.6 lens is labeled (in small print) 48, while the scale for the 250mm f6.3 is marked 49. They both use the same #1 shutter and have scales on both sides of the shutter. While they are physically interchangeable, they are not functionally interchangeable.

Scales can sometimes be interchangeable, but be very careful. As Dan said, they are lens (and shutter) specific. The positioning of the maximum f-stop varies on the scale -- and the width of the scale does as well.

[norly]

The scales fit perfectly, and if the actual shutter is the same, then it should work I think.

But as you mentioned, the scales has different lengths and values, but the two retaining screws are at the same position.

[xkaes]

It doesn't matter if the scales physically fit. What matters is if the same f-numbers are in the same location on the shutter. They might be -- if you are lucky.

I can swap the #48 and #49 Fuji scales on the same shutter, because they are both the exact same size, but the exposures will be all wrong -- if they are used for a lens they were not designed for.

[sharktooth]

You can do an easy check. Look through the lens at the diaphragm when set at it's widest aperture. You should see a full opening (or a very very slight closing of the diaphragm. When set at anything smaller than its widest aperture, you should see the diaphragm closing.

If the diaphragm is more than a tiny bit closed at the widest aperture setting, or is still wide open at the next smaller aperture setting, then the scale isn't correct.

[xkaes]

That won't tell you if the scale is correct. When the shutter is open all the way, some scales should show f5.6, some f6.3, some f4.5, etc. The f-numbers on the scale have to be correct -- and at the specific location. That depends on the focal length of the lens and the shutter.