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Dustyman
14-Oct-2016, 13:31
I just received a lovely Sinar shutter that I will use for older barrel lenses. It is mounted, as is typical, just behind the front standard will work fine for many lenses. I can see, however, the possibility that some lenses might extend too far into the camera and won't be able to clear the shutter blades. Aside from conical lens boards, the thought of using a third middle standard to support the shutter came to mind. That way, there would be a bellows in front of it that would solve the clearance issue.

I'm using an 8x10 P2. I guess I would add an "F" standard (to support the shutter) and a normal 4x5 bellows for the front half. Then the "P" standard would support only the lens.
I will not be using, obviously the aperture control feature of the shutter for these old lenses.

Has anyone done this, and are there any pitfalls that I should be aware of?

Would this scenario also allow me to use lenses that have larger rear elements than the shutter opening, since the shutter would be further back and the light will be converging smaller at that plane?

Daniel Unkefer
14-Oct-2016, 18:52
Sinar recommended that the optimum position of the rear lens cell should be about 1mm from the shutter blades. With lenses that had protruding rear cells, they would "forward mount" the lens, so the rear cell would be at that optimum distance. I've done it with quite a few of my lenses.

Oren Grad
14-Oct-2016, 19:26
I picked up an intermediate standard for my Sinar kit in part for this reason. I set it up the extra standard with Sinar shutter that way once as proof of concept, though I haven't yet tried making any pictures with that configuration and so can't report on any surprises in implementation. My idea was to use a bag bellows between the front standard and the shutter-bearing intermediate standard, to allow the rear element to be moved as close as possible to the shutter.

Peter De Smidt
14-Oct-2016, 22:29
Make spacers for your lenses. Shim them out on the lens boards. It's not hard.

Daniel Unkefer
15-Oct-2016, 18:33
Just a thought. It is not a good idea to hang a heavy lens directly off the front of the shutter. Sinar made a mounting plate (Norma) to screw directly into the shutter front threads, but I have never seen one for sale in thirty years. I'd like to buy one if I could find one. I have always resisted having one made. I always thought they were for smaller barrel lenses and of limited use.

The mount cannot support a heavy lens.

Peter De Smidt
15-Oct-2016, 18:55
That depends on what you mean by "heavy". Sure, at some point heaviness would be a problem, but it's not using the 17" Collinear, a 15" Aviar, or a similar-sized lens. Those are fairly substantial lenses compared to many LF lenses.

Armin Seeholzer
16-Oct-2016, 02:39
I just received a lovely Sinar shutter that I will use for older barrel lenses. It is mounted, as is typical, just behind the front standard will work fine for many lenses. I can see, however, the possibility that some lenses might extend too far into the camera and won't be able to clear the shutter blades. Aside from conical lens boards, the thought of using a third middle standard to support the shutter came to mind. That way, there would be a bellows in front of it that would solve the clearance issue.

I'm using an 8x10 P2. I guess I would add an "F" standard (to support the shutter) and a normal 4x5 bellows for the front half. Then the "P" standard would support only the lens.
I will not be using, obviously the aperture control feature of the shutter for these old lenses.

Has anyone done this, and are there any pitfalls that I should be aware of?

Would this scenario also allow me to use lenses that have larger rear elements than the shutter opening, since the shutter would be further back and the light will be converging smaller at that plane?

Yes I did it some years ago as long as you are not tilting/shifting its not a big problem, but I used a bag bellows to get as near to the lens as possible! It works only with long lenses good with wide ones you get vignetting! But as soon as you want shooting with a normal mounted lens you have to change the whole setup this was a no go for me. So I sended the lens to Sinar for mounting it for normal use with the behind the lens shutter. I was very expensive about 400-500 SFR 10 years ago! But Sinar is not anymore here in Switzerland!

cowanw
16-Oct-2016, 10:14
I have done exactly this on my Cambos and it works well enough. For shift and tilt you are best to loosen all the knobs on both standards and move the assembly by hand to point the way you wish.
Yes the lens can be vignetted at wide open and you could loose a stop in the corners which is OK with portraits. but of course a smaller f stop alleviates this.One of my shutters is a 5 inch Packard with a shell around it for light tightness and two front standards. It is very doable

Dan Fromm
16-Oct-2016, 10:32
Hmm. The lens can be mounted on a tube, as has already been mentioned, and can be supported by a crutch, as I don't think has been mentioned yet.

Not directly relevant since I don't use Sinar gear or an adapted Sinar Copal shutter but that's how I attach my 900/10 Apo-Saphir to a 2x3 Cambo front standard. The crutch, a modified (polite way of saying seriously mutilated) Cambo front standard, bears most of the weight.

Greg
16-Oct-2016, 13:17
I've mounted the shutter in front of the lens then draped the dark cloth over the shutter and lens when I made the exposure. Have never experienced fogging or light leaks on the negatives. Fortunately my barrel lenses all have front diameters smaller than the circular opening in the Sinar shutter.

Stephen Thomason
16-Oct-2016, 16:51
Yes, add a middle standard, as I did. I simply use a standard from one of my F's, it doesn't have to be the dedicated auxillary standard. I use a bag bellows from the middle standard to the front standard. At today's prices, complete F's are almost free.

Dustyman
27-Oct-2016, 08:52
I wanted too thank all who contributed their experience with this, and also share my findings.

When mounted to the Sinar standard, there is 5mm clearance between the back of the lens board and the shutter housing. (The distance is considerably greater to the actual shutter leaves, but since my lens (36cm Heliar) is wider than the shutter opening I am only concerned if it hits the shutter housing.)

I have several different cameras I shoot with in addition to the Sinar, so instead of wasting my only flange on a Sinar board, I am having SK Grimes thread a lens board directly. Using a spacer ring will reduce the rear cells' protrusion through the rear of the lens board to a bit under 5mm so it will just clear the shutter housing when attached.

The only remaining problem was the auto aperture pin which extends forward 4mm and would have hit the back inside edge of the lens. This pin was easily removed. Four tiny screws open the shutter housing. The geared ring that the pin is attached to simply lifts out. I stored it for possible future use with DB lenses.

That should do it. Awaiting the threaded board to test.

DrTang
27-Oct-2016, 10:41
hahah - I just snapped that pin off mine

also..I made a crude-man style spacer for my lenses: long bolts from the back, plastic spacer tube stuff from the hardware store, then the mounting ring - then I made the thing light tight with black gafferes tape - the thing looked like hell, but worked

Dustyman
27-Oct-2016, 11:16
Yeah, I considered snapping the pin off as well. Opening the housing, a last ditch effort, turned out to be super easy. So if you happen to get another shutter, now you know : )


hahah - I just snapped that pin off mine

also..I made a crude-man style spacer for my lenses: long bolts from the back, plastic spacer tube stuff from the hardware store, then the mounting ring - then I made the thing light tight with black gafferes tape - the thing looked like hell, but worked