PDA

View Full Version : Mounting lenses onto Sinar Auto Aperture Shutter



Anthony Lewis
8-Sep-2007, 04:44
I want to take portraits with my Sinar 4x5 camera. I am trying to reduce the time, and fiddling about, between when the subject is set to firing the shutter. So I am looking at purchasing the Sinar Auto Aperture Shutter which mates with Sinaron lenses in DBM mounts.

However all my lenses are either Schneider or Fuji. I do not want to change their mounts to DBM either. I know Sinaron lenses with Copal between-the-lens shutters can be used with the Sinar Auto Aperture Shutter, with the disadvantage of setting the aperture manually. This would be OK by me, if after inserting the dark slide, I would then only have to set the aperture - this would still speed up the picture taking process.

My question is, can I mount my Schneider and Fuji lenses onto the Sinar Auto Aperture Shutter? I believe Sinaron lenses have some sort of tube on the lens plane for this purpose, but I donít know what this means. I feel someone out there knows the answer to this, or can give me suggestions. Thanks

Bjorn Nilsson
8-Sep-2007, 07:27
You can use any lens for this as long as the back element of the lens doesn't protude into the shutter blades. That distance is 18.5mm behind the lensboard (just shy of 3/4"), but do check for yourself with the lenses you intend to use.
There is an older version of the Sinar Copal shutter (from the Norma days) which doesn't have the aperture control. That shutter works in exactly the same way as the newer shutter which have the DB control added on, so from the beginning there was only the shutter as such and every user had to set the aperture manually, before each shot.
E.g. normal 150mm Symmars doesn't protude into the shutter, nor does the Fujinon A 240mm (if that is what you have).
The real fun begins if you can find an adjustable iris lens mount, which Jim Galli and others are using for their arsenals of old lenses. Then you can use just about any old lens, including brass lenses etc., without having each and everyone mounted before you can use it. These old lenses are usually very nice for portraiture, as they are softer than modern lenses at wide apertures.

mikec
8-Sep-2007, 07:43
When using the auto aperture shutter config, lenses aren't mounted on it, but in front of it. Maybe a typo on your part. If your lens boards are flat then you only have
19mm between the board and the shutter blades to play with. I guess that most of your lenses rear elements protrude more than that from the back of the board, so you would need to swap them for boards with a forward recess, which is how Sinar got round the issue. These are pictured on the Sinar site , but I couldn't find part numbers. I expect someone else here will know.

thedeep
8-Sep-2007, 09:08
you could probably "recess" the shutter instead of getting new boards for your lenses since you're rigging it more or less. Maybe stick a set of throwaway glued together bellows between the standard and the shutter.

Struan Gray
8-Sep-2007, 12:03
As thedeep says, when a lens projects too far to the rear I mount my shutter on an intermediate standard. Actually, I mount it backwards so that I can get the shutter blades as close to the rear elements as possible. I use a second bellows to seal the gap between the front standard and the shutter. As BjŲrn says, it works well with an iris lens holder too: you don't need coned lensboards in odd thread sizes to try out all those oddball brass lenses you bought from that guy in Nevada.