Question re Sinar Auto Shutter

[Richard K.]

I'm thinking of adapting a Sinar Auto Shutter to use IN FRONT of the front standard, for barrel lenses in the following way: there is a Sinar adapter the shutter attaches to (from a gentleman in Hong Kong) and the other side of the adapter fits like a lens board on the front standard. The screw-in opening on the shutter front will take a Technica type adapter(screw on one side, regular clips on other to hold lens mounted on Technika boards). See:


http://cgi.ebay.com/Sinar-shutter-spacer-Adapter-for-5x7-8x10-film-camera_W0QQitemZ150403661620QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2304c1bf34

and


http://cgi.ebay.com/Linhof-lens-board-on-Sinar-shutter_W0QQitemZ150403355179QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2304bd122b

My questions: seems like this should work? The gentleman is also working on a Sinar 5.5" adapter - this would be better than the Technika, since it would allow for bigger diameter barrel lenses to be mounted than on the Technika board, no?

This seems like a better arrangement than between standard and bellows since it is more portable and less disruptive of camera, albeit requiring a modest investment in 2 adapters.

Auxiliary questions re the Sinar Auto Shutter:

Is there a controlable aperture on this shutter or are those f stop numbers on the side display a reading when a lens is coupled to the shutter? Why is there a screw in hole on the shutter front? What was it (the threaded hole) originally for? Is the intended use for this shutter to go between front standard and bellows? Then I guess this could work too with barrel lenses mounted on Sinar boards and no protruding rear elements placed directly in the usual way onto the front standard?

Sorry if this is a bit unclear; it reflects my unfamiliarity and confusion regarding this type of shutter.

Thank you for your help!

[Richard K.]

I meant to ask (more specifically): with the Auto Shutter mounted between front standard and bellows, what is the use of the threaded opening on the shutter front?

[Lachlan 717]

Richard,

I don't use mine with DB mounted lenses, so I am
not sure how they connect to the shutter. They could use some of the holes/threads etc that you mention.

One thing that I did want to draw your attention to is one benefit of mounting the shutter behind the front standard:

If you have a lens whose rear element extends behind the mounting flange, you get some space. If it is in front, you'll need a "Top Hat" lens board. Otherwise, you risk jamming the lens into the shutter blades.

I firmly believe that the shutter behind/iris clamp in front is the best way to do this (the clamp providing further room behind the rear element).

[Richard K.]

One thing that I did want to draw your attention to is one benefit of mounting the shutter behind the front standard:

If you have a lens whose rear element extends behind the mounting flange, you get some space. If it is in front, you'll need a "Top Hat" lens board. Otherwise, you risk jamming the lens into the shutter blades.

Good point. I guess there are lenses where even your set-up won't work- i.e. they protrude way beyond the flange? I do get some relief from the shutter to standard adapter, about the same as the thickness of the front standard in your case but not with the iris clamp...what is that anyway?:)

[Lachlan 717]

Good point. I guess there are lenses where even your set-up won't work- i.e. they protrude way beyond the flange? I do get some relief from the shutter to standard adapter, about the same as the thickness of the front standard in your case but not with the iris clamp...what is that anyway?:)

It's a strong metal iris that, as the name suggests, clamps the lens in place. It is used in place of a specific lens board.

If you search here under "Universal Iris Clamp", you should find some photos. Keep in mind that these aren't small; mine's on a Sinar lens board.

I can post some photos later if you want. If you search for a Thead that I posted recently showing my new Shen, there is a photo of my set up (showing the shutter, clamp and Petzval in situ).

[mikec]

The shutter shown in item for the spacer does not look like an auto aperture shutter.
At least it is not like mine. My auto aperture shutter has a coupling pin which is proud of the shutter face which pushes on a leaver on DB mounts to close the diaphragm . I do not see how the Linhof style adapter takes this into account. Maybe the threaded sleeve is long enough to be able to safely leave the pin free from touching the adapter. The seller does say it would filt all Sinar shutters though, so he should know.
I wouldn't use it if there was a chance of accidentally pushing the pin into the body.

I do not know why the shutter has a threaded aperture, possibly for some filter holder, though behind the lens is not where I would have them.

The Auto shutters are settable. There is a setting nob coupled to the indicator so you can tell what f-stop you are using. It indicates the taking aperture as the viewing is normally done with the aperture fully open, thus the term "Auto". It is designed to go between the front standard and the bellows.

[Steven Tribe]

There is no doubt that the mounting of the sinar copal behind the lens board is an attractive aesthetic solution - if you have only a few taking cameras and limited size barrel lenses. But the double lens board (different types/step-up/distance piece) is more adaptable for wide lenses and multiformats. The original sinar copal (in green norma livery) is a bit nicer to work with as it without the (superfluous for us) side adjustment panel for F setting. I enclose images of the two types below. The basic body shapes are identical.

[Lachlan 717]

But the double lens board (different types/step-up/distance piece) is more adaptable for wide lenses and multiformats.

Steven,

Can you please elaborate on this?

It doesn't seem to be correct as far as wide lenses go as you are moving the lens forward half the thickness of the double lens board. Wouldn't this mean needing recessed LBs to compensate the increase of Film to Flange Distance?

Or, do you mean the width of the actual lens, not the focal length?

Can you please explain the "multiformats" adaptability?

Thanks in advance,

[Ken Lee]

I have a Sinar Shutter like the one on top. It fits into the read of the standard, and the bellows fit into its rear.

Some lenses are too wide to mount on a Technika board. I mount those on a Sinar board. Other lenses are rather small, and are mounted on Technika boards. When using them, I place a Sinar-Technika adapter on the front of the standard.

Even when using barrel lenses, the Sinar shutter needs some clearance between it and the rear of the lens - because the shutter has some pins which protrude forward, which need to move freely.

As pointed out, some barrel lenses may be mounted in such a way that their rear would ordinarily touch the shutter mechanism or interfere with the movement of the pins. They need to remounted with spacer rings, so that they sit forward of the shutter. These lenses are not just the big ones. Even a rather small lens can interfere, if its rear sits back too close to the shutter.

So, if you plan to mount the shutter in front of the lens, make sure that those pins face away from the lens.

Care is needed, since the shutter is not designed to be exposed to the elements. When not in use, I always cover mine with an empty lens board, for protection. That's another reason why it's best to place it between the bellows and the standard: it won't get damaged.

I were adapting it to another camera, I would try to use it as designed: behind the front standard, and in front of the bellows. In fact, I have often thought about getting something made for my old 5x7 Kodak 2A.

[Hugo Zhang]

Richard,

I looked at Sinar Auto Shutter before I settled with my Packard shutter box for reason that Sinar Auto shutter couldn't accommendate lenses of large diameter like a Heliar 36cm. Go find an universal iris clamp.

Here is a picture of my "Dan Dozer Packard shutter box" with my Kodad 2D camera.

Hugo

[Steven Tribe]

Width meaning physical width of diverse barrels and flanges - not focal length. Adaptibility means that once the double spaced lens boards get into production you can go from sinar mounted boards to linhof, sinar to cambo. Of course, you loose some F but I would be doing that with the with the sinar shutter alone.

[Steven Tribe]

Dear Hugo.

"I looked at Sinar Auto Shutter before I settled with my Packard shutter box for reason that Sinar Auto shutter couldn't accommodate lenses of large diameter like a Heliar 36cm."

Well I have the Heliar 36cm mounted on a sinar board which works well with a sinar copal. It has been blocked up about 1cm on the flange by a previous owner.

[Ken Lee]

I too, used a 360mm Heliar with the Sinar Shutter. As Steven mentioned, it merely needed a spacer ring. I had one made at a local machine shop, and it all fit nicely on a Sinar lens board.

[Lachlan 717]

Width meaning physical width of diverse barrels and flanges - not focal length. Adaptibility means that once the double spaced lens boards get into production you can go from sinar mounted boards to linhof, sinar to cambo. Of course, you loose some F but I would be doing that with the with the sinar shutter alone.

I just use a Sinar-Linhoff lens board. These have been around for ages. The Linhof part is recessed into the Sinar one, so I don't lose any Film to Flange Distance (admittedly, I only have 1 barrel lens on a Linhof board).

For my other barrels/brass, I use a universal iris clamp mounted on a Sinar board. The shortest of these lenses is 5", so I have no issue with rear proximity.

As for lens width being a limitation, I think others have covered this off as not being an issue except for very large lenses, and I would think that the f5.6 aperture limitation of all but the newest shutters would limit these before the mounting location would.

[Steven Tribe]

Sounds sensible Lachlan. I just have to go up to the cambo board size as I have flanges diameters up to 16cm ( + lens weighing under 2 kilos) for which a self-made solution is necessary. Or is there a sinar/cambo combi board available?

[Lachlan 717]

Sounds sensible Lachlan. I just have to go up to the cambo board size as I have flanges diameters up to 16cm ( + lens weighing under 2 kilos) for which a self-made solution is necessary. Or is there a sinar/cambo combi board available?

Not sure, Steven.

I've never had cause to look.

Mind you, an Iris Clamp that has a 160mm opening will be a big, heavy piece of metal... If there is such a thing!

I wouldn't think it too difficult to fabricate a Sinar/Cambo combi. I would think that you could easily attach one to the other. When I mounted the iris, I cut a "grummitt" from a 3mm piece of rubber. This acted as a lightproof seal as well as helping to grip. I'd recommend this to anyone mounting one, and to you if you're going to attach one lens board to another.

[Steven Tribe]

I don't want to go the way of the iris clamp when I have a lot of good flanges. In my view they are OK for testing objectives but I would prefer to invest in a series of lens boards and adapters made for the objective sizes that fits the cambo. I think the free space needs to be about a few mm. The sinar board locking catch can be pushed up and down if the relevant cambo corner is cut off at an angle.

[David McNiven]

By attaching the lens to the shutter instead of the front standard the (small!!) screws which hold the shutter together would also have to carry the weight of the lens.

With DB & DBA mounted lenses the thickness of the front standard between lens-board & shutter is necessary to maintain the correct distance between the aperture control (stop-down) levers on the shutter & on the lens.

You can check out the size of the screws and the construction of the shutter by looking at the exploded diagram in the shutters .pdf at Sinar or at image2output.

I believe some people have used these shutters on the front of lenses with adaptors between the lens filter ring and the threaded section of the shutter.

[Steven Tribe]

Thanks for the cautionary note. I have checked the norma and later versions and it is clear that in both constructions the 4 small screws at the edges of the rubber gasket are the weak point. The cast casing and plastic seem to have a great deal of integral strength. I think the sinar/copal will hold up to the couple of kilos I am planning to put on the front. They are not long objectives so the torque isn't near what it would be with a Petzval objective. I will be checking the two screws holding the top locking strips too as I think these may be suspect. Front mounting wouldn't work for me because of extreme diameters.

[Struan Gray]

Steven, if you have a spare Norma auxiliary standard consider cannibalising it for the frame: it makes a nice compact lensboard-to-lensboard joiner.

[Steven Tribe]

The thought has occured to me and I already have picked up an extra Cambo intermediate but a Sinar hasn't come my way yet. Perhaps inter-connecters were made separately without the standards/mount?