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salfavata
11-Feb-2019, 01:42
I have a chance to purchase a used 90mm Super Angulon f8 (Linhof variant) here in France, and it has a Copal 0 shutter in the latest all-black version. However, the aperture scale on the shutter extends to 5.6, and the aperture mechanism does indeed open to 5.6. but no longer reveals the seven-sided polygonal shape from the aperture blades.

There is a Rodenstock quality seal on the shutter so it is not the original.

Questions: 1. on two different focal length lenses with different aperture ranges, could the Copal 0 shutter be interchanged with the other lens without exposure issues? 2. Or are somehow the apertures at each f-stop appropriate for a particular focal length lens?

Lens is in beautiful condition, no Schneideritis. Thanks.

Dan Fromm
11-Feb-2019, 08:06
Oh, dear, another instance of the question that won't die.

Aperture scales are lens specific. A good repairman -- in the US, SKGrimes, for example -- will have the pre-made aperture scale you need or, if necessary, can engrave a scale on the shutter. For you, Gerard Metrot in Paris comes to mind, but I'm not sure he's still working and don't have his contact information. Ask on galerie-photo.info

Lachlan 717
11-Feb-2019, 08:08
The scales are interchangeable along with the lens elements.

Two screws hold the scale in place. The markings relate to where the aperture knob movement brings the blades into the path of the light through the lens.

This will be at a different spot for different lenses.

Bob Salomon
11-Feb-2019, 08:12
Just as important the lens may or may not require shims for proper spacing between the front and rear groups. If someone just switched shutters you will probably find that there is also a shim issue. That would effect performance!

pepeguitarra
11-Feb-2019, 08:46
My experience with the all-black (the latest) copal has not been good, they are the ones with the speed going off most of the time. The old ones behave better in my case. I have not seen any problem moving from one Copal to another Copal equivalente. Three of my lenses have scales on white paper I glued on to them. I learned to calculate the scale from the book: Using the View Camera by Steve Simmons. You can get the book in Amazon for less than $15, or new (I think they still sell it), it is the best book on LF.

salfavata
11-Feb-2019, 13:06
Ahh. I see that I didn't do a good job explaining myself. It's not about physically replacing the scale itself, but related to exposure.

In other words, if my meter says f16, and I set the aperture at f16 on this lens, could the exposure potentially be off because this Copal 0 came from a lens with a wider aperture range, and/or perhaps a different focal length?

I've been doing LF for 40 years, this never occurred to me. If I were in the U.S., be a no brainer... just test some film. But things are a bit more challenging here, and LF film/processing is expensive. Thoughts?

Bob Salomon
11-Feb-2019, 13:19
Ahh. I see that I didn't do a good job explaining myself. It's not about physically replacing the scale itself, but related to exposure.

In other words, if my meter says f16, and I set the aperture at f16 on this lens, could the exposure potentially be off because this Copal 0 came from a lens with a wider aperture range, and/or perhaps a different focal length?

I've been doing LF for 40 years, this never occurred to me. If I were in the U.S., be a no brainer... just test some film. But things are a bit more challenging here, and LF film/processing is expensive. Thoughts?

Yes, it will. You need the proper scales.

Leigh
11-Feb-2019, 13:23
In other words, if my meter says f16, and I set the aperture at f16 on this lens, could the exposure potentially be off because this Copal 0 came from a lens with a wider aperture range, and/or perhaps a different focal length?
The aperture is actually defined as a fraction of the focal length, written either as f/n or f:n.

These mean the aperture diameter equals the focal length 'f' divided by f-number 'n'.

Theoretically, if you change the cells on a shutter to those of a different lens WITH THE SAME FOCAL LENGTH, the aperture scale will be reasonably close. If the new lens has a different focal length, the scales will be WAY off.

- Leigh

salfavata
11-Feb-2019, 13:27
I thought the exposure would be off, but math is definitely not my forte. Thanks for the help!

B.S.Kumar
11-Feb-2019, 16:28
https://www.largeformatphotography.info/forum/showthread.php?139119-Some-Questions-and-Observations-About-Making-an-Aperture-Scale

Kumar

JimL
11-Feb-2019, 16:39
The best situation would be if the shutter was from a 90mm f5.6 lens. With the shutter blades open, hold the lens at arm's length, looking straight at the front side. Close the aperture slowly until you just see the aperture blades appear. Look at the reading on the scale - if you're close to the f9 mark, then you can probably use the scale as is. If not, you'll have to either get the right scales or make a sticker as pepeguitarra suggested.

salfavata
14-Feb-2019, 04:07
One last thought... for review, this is a Super Angulon f8 #13274037 mounted in the latest version of a Copal 0, but with widest aperture at 5.6. And the Copal had a Rodenstock Quality Seal on it.

OK. I noticed the aperture scale has a series of minuscule digits: 0011.067. This may be a part number linking the Copal to it's original Rodenstock lens... whatever that was?

Bob, if that's the case and based on this number, have any idea what the originating Rodenstock lens this may have been. The 3 digit code for the 120mm Macro, 135mm and the 150mm Copal 0 5.6 variants are different.

Kumar: thanks for the excellent link and info, but the calculations and procedures are well beyond my meager mental capacities. I'm just a very old man with a brain hard-wired to art and little else at this point. ;)

salfavata
14-Feb-2019, 04:15
JimL. Thanks. Just checked. As I slowly move the aperture blades from 5.6 toward smaller apertures, I don't see any blades until the adjustment pointer gets to the f8 indicator. Then the polygonal shape begins to emerge.

So, what does this mean? Thanks!

B.S.Kumar
14-Feb-2019, 05:12
f/8 of the lens is right at the point where the aperture blades just begin to appear. After that you can either follow the instructions in the post I linked to, or sacrifice a test roll to see if the other markings are within your tolerance limits.

Kumar

Bob Salomon
14-Feb-2019, 05:27
One last thought... for review, this is a Super Angulon f8 #13274037 mounted in the latest version of a Copal 0, but with widest aperture at 5.6. And the Copal had a Rodenstock Quality Seal on it.

OK. I noticed the aperture scale has a series of minuscule digits: 0011.067. This may be a part number linking the Copal to it's original Rodenstock lens... whatever that was?

Bob, if that's the case and based on this number, have any idea what the originating Rodenstock lens this may have been. The 3 digit code for the 120mm Macro, 135mm and the 150mm Copal 0 5.6 variants are different.

Kumar: thanks for the excellent link and info, but the calculations and procedures are well beyond my meager mental capacities. I'm just a very old man with a brain hard-wired to art and little else at this point. ;)

No, but you are in the EU as is Linos. Just call their service center and ask them.

salfavata
14-Feb-2019, 12:57
Thanks, Bob... but I don't know what "Linos" is. Can you give me a bit more to go on? Many thanks.

Bob Salomon
14-Feb-2019, 13:53
Thanks, Bob... but I don't know what "Linos" is. Can you give me a bit more to go on? Many thanks.

Rodenstock Precision Optical is a division of Linos and both are owned by Qioptiq. Just do a google search. They are in Germany. You do not want the Russian site.

salfavata
14-Feb-2019, 14:45
Thanks everyone. After comparing many pics for Rodenstock Copal 0 lenses on ebay, I finally determined this shutter came from a 135mm Sironar-N. The minuscule "code" matches exactly as do shutter/aperture indicators on both sides of the Copals.

The shutter/aperture indicators on a SA 90mm f8 Copal 0 are substantially different, so impossible to expose film correctly with this mismatched Copal 0. I'll put the topic to rest. Thanks again.

Bob Salomon
14-Feb-2019, 14:48
Thanks everyone. After comparing many pics for Rodenstock Copal 0 lenses on ebay, I finally determined this shutter came from a 135mm Sironar-N. The minuscule "code" matches exactly as do shutter/aperture indicators on both sides of the Copals.

The shutter/aperture indicators on a SA 90mm f8 Copal 0 are substantially different, so impossible to expose film correctly with this mismatched Copal 0. I'll put the topic to rest. Thanks again.

Same scale on the Apo Sironar N and Apo Sironar S 150mm also.
But you could contact Schneider in Bad Kreuznach and see if you can just buy the proper set of scales.