Sinar Copal Shutter - f4 or f5.6?

[cdholden]

I now own a Sinar Copal Shutter. I've seen some that have a maximum aperture of f5.6, others at f4. After reading the directions, I still have a few questions:
1) Is there any functional difference between the two, or basically the same?
2) Is there a difference in diameter between the f4 and f5.6 versions? If so, how much different? ...or is it just an interchangeable iris scale?
3) Why is the inside of the shutter hole threaded?
4) Where does one find the cable that automates shutter closing with insertion of film holder?

I look forward to this addition for more exposure control, as well as now having flash sync with barrel lenses.

Chris

[Steve Smith]

The actual F No. depends on the focal length of the lens fitted to it.

F No. is roughly equal to focal length divided by the aperture diameter.


Steve.

[Frank Petronio]

I've never had the f/4 version so I can't answer, other than to say they work identically.

The cable that attaches to the film back is or was still available from Sinar in NJ, or perhaps from B&H, etc. it is not cheap I remember. I once had things set up that way, with a rare sliding back. It was a pain to set up but once you got it going you could crank!

You need a big heavy tripod because you'll be rockin... try not to think about how expensive film is.

[GeorgesGiralt]

Hello !
If I'm not mistaken, the F-stop difference is only a different scale fitted into the slot.
As the knob actuate the push pin for the DB mount lens, you select the scale corresponding to the max aperture of the lens being used. So, when you look from the back of the camera, you'll see what F-Stop the lens is set at.
Of course, the system will work fine if you've a F:4.0 lens and a 5.6 scale. You'll have to make some mental calculation ;-) to find what stop you're actually using !
As per the thread, I think that at one point, Sinar sold filters to fix to the shutter itself. (preventing scratches and the like...) So maybe this thread is/was used to fix them.

[Sevo]

As far as I know, DB lenses will work in both f/4 and f/5.6 shutters without needing readjustment, so it probably is not only the scale, but also the aperture control lever that got modified.

Personally I never saw a point in getting a f/4 Copal - all my odd lenses faster than f/5.6 are barrel types and not DB mountable with reasonable effort, so that the older versions work just as well.

[Frank Petronio]

The 75 and 90/4.5 Rodenstock Grandagons were out when the f/4 shutter was released.

Personally I never understood why anyone would use the DB mount at all but someone must have believe the crazy marketing rationale for it ;-p

But in the real world, mount the lenses on flat boards, attach the shutter to an extra standard and mount a spare bellows between the shutter and the front standard. Send me the $100s of dollars I just saved you.

[Sevo]

Personally I never understood why anyone would use the DB mount at all but someone must have believe the crazy marketing rationale for it.

In the studio scenario they were devised for, DB mounted lenses did speed up work - they do away with the need to stop down. Originally, they were cheaper than shutter mounted lenses, too - but when the Zeiss subsidiaries got real competition from Copal, that difference evaporated.

[Ken Lee]

Personally I never understood why anyone would use the DB mount at all but someone must have believe the crazy marketing rationale for it ;-p

But in the real world, mount the lenses on flat boards, attach the shutter to an extra standard and mount a spare bellows between the shutter and the front standard. Send me the $100s of dollars I just saved you.

The shutter is small and light, and requires neither a spare bellows nor an extra standard. Those items cost money too. They are large, require additional setup time, and make the camera harder to carry around :)

Here's a Sinar P that I carry in a simple canvas tote bag. The Copal shutter stays on the front. You can barely tell it's there.

http://www.kenleegallery.com/images/forum/gear.jpg

[rdenney]

Ken, you need the additional standard if you mount a lens with a large rear cell on a flat board. The lens has to sit in front of the shutter. Putting the shutter on an intermediate standard allows you to move the shutter far enough behind a lens with a protruding rear element, without using a DB mount.

The difference between the f/5.6 and f/4 versions is the scale and also the aperture actuating pin. The DB mounts provide a compatible control for their diaphragm, and the f/4 versions just have more range of motion on the wide end. That keeps f/5.6 and slower lenses compatible. Those pins just don't move as far, but they are always compatible with the shutter. As far as I know, they all have the same size opening.

It seems to me that the whole point of the integral shutter when used with the DB-mounted lenses was to mechanically automate the camera so that it could compete in convenience with medium-format cameras of the day. The idea was to provide shutter speed and aperture control from the photographer's position behind the camera, to open the shutter and aperture automatically for composing, and to close the shutter automatically when a film holder was inserted. For most of us, these advantages are not all that relevant to our requirements.

Of course, the real advantage to the shutter for most of us is the ability to mount barrel lenses, or to work around a lens with a faulty shutter. Most barrel lenses don't protrude to the rear significantly, so they will usually sit in front of the shutter when it is mounted normally on the back of the front standard. The shutter also has a really useful range of speeds--1/60 to 8 seconds, which sits right where most of us need a shutter to sit. And if we use it for all our lenses, we only have to learn the foibles of one shutter.

The second cable is not needed for operation, by the way, unless you really need the shutter to close when you insert the film holder. The shutter will work just fine without it, as long as you remember to close the shutter yourself (and the press focus control is quite visible from the rear, in addition to the shutter-open warning pin protruding from the top). That cable has a specialized fitting on both ends, so there is no way to make something else work. The essential cable for any operation is the main cable release, which is also specialized, though perhaps easier to reproduce.

Rick "hoping to experiment with his recently acquired Sinar shutter in the next week or so" Denney

[Brian K]

The 75 and 90/4.5 Rodenstock Grandagons were out when the f/4 shutter was released.

Personally I never understood why anyone would use the DB mount at all but someone must have believe the crazy marketing rationale for it ;-p

But in the real world, mount the lenses on flat boards, attach the shutter to an extra standard and mount a spare bellows between the shutter and the front standard. Send me the $100s of dollars I just saved you.

Frank, I have the f4 and f5.6 sinar copal shutters as well as the Expolux shutter and monitor. In the studio compared to using normal lens shutters, the sinar copals were far faster. This speed was due to the DB mounts enabling the opening and closing of the shutter when the film holder was removed as well as being self cocking. I would be able to quickly look through the camera between exposures without having to stop and open the shutter,look and then close the shutter. this came in really handy when shooting people or food with LF.

The expolux with monitor enabled you to do incredibly precise on the film plane spot metering of a scene, take multiple readings, highlight, shadow , etc and then would plot the values and give you the exposure to get it all perfectly. However it was slower working than the sinar copal shutters because the shutter opened and closed electronically between exposures and it did so in a very precise manner.

[cdholden]

Thanks for your input, everyone.
As Rick suggests, I do not have any DB lenses but do have several barrel mount lenses. I can use the barrel's iris for aperture and just use the shutter for exposure and flash sync.

[Frank Petronio]

this came in really handy when shooting people or food with LF.

Oh I understand and agree and have seen how it would have been great back in the days of shooting 4x5 catalogs shots 10-100x per day.... Those were the days....

But just thinking in terms of this forum, I don't know anyone who works like that anymore. I figured he was looking for a way to mount old/cheap lenses as efficiently as possible, without sourcing and setting up the DB mounts.

[Ken Lee]

You can use 3 kinds of lenses with the Sinar shutter: those in barrel, those on a DB board, and already those mounted in a shutter.

I even re-mount some of my shutter-mounted lenses (Sironar, Fujinon), on DB boards (and put them back in their shutters when using my wooden non-Sinar camera).

Using DB boards in the field saves time and prevents errors. The shutter is self-cocking, so you never have to deal with that issue. You can tell whether the shutter is open or closed, even after the film is loaded, without having to walk to the front of the camera and peer into the lens. The camera can be operated entirely from the rear. You can even get a nice "depth of field preview" by squeezing the cable release gradually.

All of this is helpful when the bellows are long (long lenses or close work), but it's a welcome improvement all the time. It takes a while to adjust to the extra steps, when you go back to shutter-mounted lenses.

[rdenney]

If I didn't already have every modern LF lens I ever wanted, it would not escape my attention that DB-mounted lenses often sell for cheap because not that many LFers have the requisite Sinar camera and shutter.

Curiosity: For those of you who have DB mounts, I'm assuming that they can be calibrated for specific lenses, given that f/11 will mean something different for lenses of different design and focal length. I'm assuming that calibration is easy so that Sinar didn't have to custom-make DB mounts for each Sinaron lens. So, can they be adjusted by the user? If so, any Copal 1 or Copal 0 DB mount will be usable with any corresponding lens cells.

Rick "who has the shutter but no DB-mounted lenses" Denney

[Armin Seeholzer]

The f4 version was introduced for the Nikon f4 65mm lens and some others so that you can use them at f4 if you like!
But I do not recomand any lens shorter the a 90 in DB or DBM mount, because the shutter also needs some space between the standards!

Cheers Armin

[Sevo]

So, can they be adjusted by the user? If so, any Copal 1 or Copal 0 DB mount will be usable with any corresponding lens cells.


Yes. Authorized dealers had a metal adjustment template marking the proper lever position for each aperture value, but it is not that hard to draw your own from an already adjusted lens in DB mount. Essentially you loosen the ring, align the lever to the aperture value corresponding to the selected diaphragm size, lock, align the end stops and are set. The process requires you to know the diameter of the diaphragm for at least one aperture value, but that is generally on the spec sheet for reasonably modern lenses, or can be reverse engineered, in desperate cases even on a entirely unmarked lens (owning a TTL meter/probe would speed that up considerably, though).

[Sevo]

The f4 version was introduced for the Nikon f4 65mm lens and some others so that you can use them at f4 if you like!
But I do not recomand any lens shorter the a 90 in DB or DBM mount, because the shutter also needs some space between the standards!

The 65/8 can be used in DB mount - that one has only a few mm movements in any case so that that limitation does not matter. But it probably is the shortest lens usefully DB mountable.

[Armin Seeholzer]

I know the f 4 65mm Nikon can also be used, but test it for your self how nice it works, and do not forgot you also can use them with a 6x9 or 6x7 back and then try to shift it!
But I still do not recomand it!!!!!

Cheers Armin

Yes 65mm is the shortest as Sinar stated!

[rdenney]

Yes 65mm is the shortest as Sinar stated!

The problem is that the lens has to be mounted so far in front of the shutter on what is in effect a cone.

I think it would be possible to adapt various retrofocus lenses of short focal length to mount in front of the shutter as a barrel lens, and still have movement capability with the Wide Angle Bellows 2. Of course, that is only valuable for using with roll film backs--those lenses will not cover 4x5 by any means.

My interest is not with wides--when I want a wide I want it to be sharp and my short lenses are modern designs and already in shutters. If I want the sort of look provided by a barrel lens of whatever vintage or type, I would be looking at a longer lens. I already have a couple that could be interesting.

Rick "noting that a wide lens with a small enough rear cell will nestle down into the cavity just in front of the shutter leaves" Denney