Copal Press shutters for Arch Apps?greenspun.com : LUSENET : Large format photography : One Thread
I am looking at getting a 72mm SA XL lens for architectural applications, and was thinking about the Copal Press shutter. I know the general specifications for the shutters, and was wondering if anyone would comment on the benefit of a self-cocking shutter for architectural applications.
I consider the lack of a 'T' setting to be a significant drawback. However, I would be willing to forgo 'T' (and also wait for a specially-ordered lens from Germany) if the concensus is that the Press shutter is worth it.
I would think that changing the filters in front of the lens will cause as much (if not more) vibration and jostling to the camera as cocking the shutter would, so I don't necessarily see the value in the Press shutter. Anyone have opinions on the subject?
-- Michael Mutmansky (firstname.lastname@example.org), May 22, 2000
One of the lenses I use for architectural shooting has a self cocking Copal Press. Is the lack of "T" annoying? If your cable release has the ability to lock (most do), it's no problem at all. Use "B". (The version of the Copal Press I have has another hole in which you can thread a second cable release to hold the shutter open but I can't seem to want to use that option)
Is a press shutter more advantageous here? Can be. Say if you need to do multiple pops with your flash because it isn't sufficiently powerful enough, multiple exposure is 'safer' and a lot more conveniently done with a self-cocking shuttered lens.
And again, if you need to use split filtration, a self-cocking shutter is very useful to minimise micro movements on multiple exposures with the same frame. Lastly, I can at least think of one other situation in which its useful to have a shutter like this - with a very deep recessed board where cocking the shutter is an inconvenient process.
(Actually, not having to cock a lens is kinda useful on its own! Though you do lose the lesser used high speeds. But with whatever system, you get used to it.)
With regards to moving the camera slightly when cocking the normal shutters, hell, it's a non issue. With a sufficiently stable and tightly locked down camera, you don't have to worry about that. As a matter of fact, I have forgotten to lock down the front rise on several occasions and there's been no adverse effect on those pictures (because the front standard on my camera has sufficient friction to stay still - and this is a very old Sinar F)
FWIW, I am myself in the process of buying a used Prontor Press shutter. According to the owner, it has a T setting. You might want to check that brand out. SK Grime's website has good details about the Prontors as well as Copal press shutters.
-- K H Tan (email@example.com), May 22, 2000.
I don't see a T setting for the current Prontors on Mr Grimes site (though I must admit to be unfamiliar with them), but the Prontor I am buying is one of their old ones. So they could be different.
-- K H Tan (firstname.lastname@example.org), May 22, 2000.
I have several lenses in Copal Press shutters for architectural work, and I very much like this setup. The lack of a "T" setting isn't a big issue with the right cable release, although there are times when it would be nice to have "T".
Worry free multi-poping is a nice benefit with the Copal Press. The main downside I found to the Copal Press was it's inability to work with most off-the-shelf air shutter releases. I've done shots in old houses with very flexible floors where it's nice to stand in another room at the end of a very long air shutter release. The de Groff air shutter release has the throw and strength to trip a Copal Press. Since I wanted the ability to hold the shutter open in "B" setting with the air release, I made some modifications to the de Groff which makes this possible.
-- Larry Huppert (Larry.Huppert@mail.com), May 23, 2000.
Thanks KH and Larry,
I was thinking that the benefits may make the press shutters worth using. Did you get your lenses in Press shutters, or did you have a lens put into a press shutter later on? I'm wondering how easy it is to make the change later on. SK Grimes site mentions that the aperture blades are at a different location in the press shutter, so I'm wondering if there are any issues with conversion.
I'll probably email SK Grimes on that question.
-- Michael Mutmansky (email@example.com), May 23, 2000.
My lens originally came in a press shutter.
Personally, I think you should get the lens in the shutter you want up front. I can't imagine that it'll be too difficult to get it remounted in another type of shutter later on, just that it'll cost you quite a bit of money! A new blank Copal shutter will easily cost you USD$200 upwards. Factor in the additional money for engraving the aperture etc.
Best to speak with Mr Grimes about the iris thingy.
-- K H Tan (firstname.lastname@example.org), May 24, 2000.
re: "Did you get your lenses in Press shutters, or did you have a lens put into a press shutter later on?"
The answer is Yes and Yes. I purchased one lens with the press shutter from the factory. The other 3 were used lenses which had standard Copal shutters. I had Steve Grimes convert these to Copal Press shutters. Steve gave me a fair trade-in for my standard Copals. I actually prefer the ones Steve converted. He engraved the scale in 1/3 stop increments. The factory new one only had full stop markings.
The other thing to be aware of with the Copal Press is that the preview is always wide open. Some may disagree, but overall I consider this a benefit. To check the effect of grad filters you have to put the shutter on "B" and use a locking type cable release. Not a big deal.
-- Larry Huppert (Larry.Huppert@mail.com), May 25, 2000.