Flash Sync for a Copal 1 Shutter

[Emerson Valley]

Does a Copal Shutter (specifically a #1) sync at all speeds? Can I shoot at 1/4 00 with it?

I plan on having a model over tomorrow and this will be the first time that I ha ve used my 4x5.

[Bob Salomon]

All leaf shutters, including a Copal 1, synch electronic flash at all speeds if it has a flash connector.

[Emerson Valley]

Thanks, Bob.

[Ellis Vener]

what flash are you using it with? If you are shooting Polaroid you should try syncing it at 1/125, 1/250th & 1/400th. If the first two are equalling well exposed (assuming no ambient light and constant aperture) and the 1/400th is darker you might be clipping part ofthe flash duration. This won't be a problem with a small flash like a Vivitar 283 but with some larger systems it might be. For instancethe Profoto Acute 2400 haas a full power flash duration (meauredat t/0.5 ) of 1/160th.

[Ellis Vener]

what flash are you using it with? If you are shooting Polaroid you should try syncing it at 1/125, 1/250th & 1/400th. If the first two are equalling well exposed (assuming no ambient light and constant aperture) and the 1/400th is darker you might be clipping part ofthe flash duration. This won't be a problem with a small flash like a Vivitar 283 but with some larger systems it might be. For instancethe Profoto Acute 2400 has a full power flash duration (meauredat t/0.5 ) of 1/160th.

[Ellis Vener]

what flash are you using it with? If you are shooting Polaroid you should try syncing it at 1/125, 1/250th & 1/400th. If the first two are equalling well exposed (assuming no ambient light and constant aperture) and the 1/400th is darker you might be clipping part ofthe flash duration. This won't be a problem with a small flash like a Vivitar 283 but with some larger systems it might be. For instancethe Profoto Acute 2400 has a full power flash duration (meaured at t/0.5 ) of 1/160th.

[Ellis Vener]

What flash are you using it with? If you are shooting Polaroid you should try syncing it at 1/125, 1/250th & 1/400th. If the first two are equally well exposed (assuming no ambient light and constant aperture) and the 1/400th is darker you might be clipping part of the flash duration. This won't be a problem with a small flash like a Vivitar 283 but with some larger systems it might be. For instance: the Profoto Acute 2400 has a full power flash duration (meaured at t/0.5 ) of 1/160th.

"t/0.5" is a measurement used to measure just the length of time the flash is emitting 50% or more light. There is another measurement, "t/0.1", which measures the length of time the flash is emitting 10% or more of the light. Both are industry standards but t/0.1 lets you know what the real motion stopping capability is ofthe flash.

[Ellis Vener]

Sorry for all the repetition, I was trying to correct grammar mistakes and then decided to add info at the end.

[David Grandy]

When you use an electronic flash with your Copal shutter make sure that you've selected X and not M. M is for bulb flash and X for electronic flash. If you select M the electronic flash will NOT synch with the shutter and your photograph will fail.

Now newer Copal 1 shutters will only have X synch - as is the case with my 300 Nikkor M. But older Copal 1's will have both X and M and - again - that's the case with my Schneider Symmar 210.

I point this out because I use my LF stuff in the field and so I rarely do any work with LF and flash. All of my other formats are modern and they just don't have M or FP synch anymore. So it's not something that I check.

Well after I ruined a sheet of Polaroid film at a recent LF studio flash shoot, I started to go through a "what happened" check list. And there it was, my 210 sitting happily on M. I checked all of my other lenses and two others were sitting on M as well, time bombs waiting to go off. Oi!

[Emerson Valley]

Ellis, I was using two SP-Systems Excalubur 3200 and a cheapo Britek 150ws for a hair light. I decided to sync at 250 like I was doing with my N90s for consistency. If that really matters.

David, The Copal 1 on my Schnieder Symmar 210 does not have either a M or X as a shutter option it goes B, T, 1 - 400. I suppose it may be a newer one that only considers Electronic Flash. Maybe?

As for my results. I plan to take them to the lab tomorrow we will see. I know that I hosed three sheets due to removing the slide with the shutter open. Grrr.

[Pete Andrews]

To reiterate what's been said already: ALL post 1960 manufacture Copal, Compur, Prontor, etc leaf shutters will synch with electronic flash at ALL speeds.Tip: If you never use flashbulbs (who does? And awyway, where can you buy them these days?) then tape the M-X synch lever in the X position. The M position is almost totally useless today.