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Songyun
3-May-2008, 09:17
What are the shutters that shares the same thread with modern copal shutters? In other words, if I have a lens in such a shutter (if broken) that I can easily replace by modern copal shutter without worrying about thread size and spacing problems.

IanG
3-May-2008, 09:46
There aren't really any standards, except modern Copal, Compur & Prontor shutters share common sizes 0, 1, 2, 3.

Ole has a list of Compound threads. Try S.K.Grimes website for others.

Ian

Ole Tjugen
3-May-2008, 10:28
Compur and Prontor shutters were "standardised" from around 1930. They came in sizes 00, 0, 01, 1, and 2; of which 0 and 1 correspond to modern Copal shutters. most dial-set Compur shutters are "specials", i.e. not compatible with anything modern. The exceptions are largely Voigtländer and Schneider lenses - these two manufacturers used "standard" sizes even before the standard was established.

Compound shutters came in several varieties of #3, #4 and #5. Neither of these correspond to the Copal #3. The dimensions of these are in the post linked to in my signature; if you look at the whole thread where that post is, you will also find the specifications for Compur #2.

Songyun
3-May-2008, 10:34
There aren't really any standards, except modern Copal, Compur & Prontor shutters share common sizes 0, 1, 2, 3.

Ole has a list of Compound threads. Try S.K.Grimes website for others.

Ian

So Synchro Compur 0, 1 is a direct interchangeable with copal 0,1, right?

Songyun
3-May-2008, 10:35
Compur and Prontor shutters were "standardised" from around 1930. They came in sizes 00, 0, 01, 1, and 2; of which 0 and 1 correspond to modern Copal shutters. most dial-set Compur shutters are "specials", i.e. not compatible with anything modern. The exceptions are largely Voigtländer and Schneider lenses - these two manufacturers used "standard" sizes even before the standard was established.

Compound shutters came in several varieties of #3, #4 and #5. Neither of these correspond to the Copal #3. The dimensions of these are in the post linked to in my signature; if you look at the whole thread where that post is, you will also find the specifications for Compur #2.

Thanks! :D

IanG
3-May-2008, 10:51
So Synchro Compur 0, 1 is a direct interchangeable with copal 0,1, right?
Ole's better at giving you a definitive answer but they should be. I've never needed to switch shutters.

All my old Compurs are without exception far more reliable than my modern Copals.

Ian

Ole Tjugen
3-May-2008, 10:57
So Synchro Compur 0, 1 is a direct interchangeable with copal 0,1, right?

Yes.

As always there's a slight caveat: There were some "special versions" of the Synchro Compurs too, which were modified to fit special lenses which needed very small cell spacing and had wide cells. But for anything even remotely normal, it's a direct fit. Even my 1928 Voigtländer Heliar 120mm f:4.5 is a direct fit in a modern Copal 0!

IanG
3-May-2008, 11:18
Ole, are you saying I can take some of my lenses out of their unreliable Copal shutters and stick them in old reliable Compur's - I guess you mean the rimset ones :D

Ian

Ole Tjugen
3-May-2008, 11:56
Ian, in one word: Yes.

As an added bonus, you get a much rounder aperture which is believed by some to improve out-of-focus rendition. :D

Kirk Fry
4-May-2008, 21:04
Don't forget that wonderful size, Copal 3s. Lots of times they leave the "s" off on the name on the outside. The mechanicals are the same size but the spacing and thread sizes are several mm different :-(. Grimes has the measurements. K

Ernest Purdum
5-May-2008, 10:39
Seiko and later Prontor shutters are also made to the same standards as current Copals. An exception I've run across is a size 1 with the back cell threads the same as the front. (I don't know why they aren't all that way.)