View Full Version : Sinar Binocular Viewer on Arca Swiss Camera

neil poulsen
2-Mar-2013, 23:46
I just finished this little project and thought that it would be worth documenting.

As you can see from the first photo, I've adapted a 4x5 Sinar bag bellows with binocular viewer to an Arca Swiss 4x5 camera.

What makes this work, is that the Arca adapter (2nd Photo, Part A. Arca Catalog #161015) is a perfect match in size to attach (with screws) to the frame of a Sinar bellows. I used a Sinar bag bellows (versus regular bellows) for flexibility. The Arca adapter attaches to the back of the Arca camera (its purpose), and the Sinar bellows with binocular viewer was attached with screws to the Arca adapter. (2nd Photo, Part B. The screws may be hard to see; they're shiny in the center photo.)

To attach the adapter to the bellows, I used 3/8" #4 screws shown in the 3rd photo. Centering the screws in the flange on the adapter centers them in the "trough" of the frame of the bellows. (Photo 2, Part C.) In fact, drilling the holes in the flange left some shards of metal that extended underneath. Serendipitously, these shards helped center the adapter onto the plastic frame of the bellows.

My process was to first drill the 8 holes in the top of the flange, adjacent to the rest of the Arca adapter. I used a 3/32nd inch drill bit. Next, I fitted the Arca adapter to the frame of the Sinar bellows using a couple of small C-clamps. (As I mentioned, the metal shards helped hold the adapter in place on the frame of the bellows. The shards fit perfectly in the trough of the frame seen in the 2nd photo, part C.) Once the adapter and bellows frame were clamped together, I extended the holes into the plastic of the frame. Drill until the bit is stopped by metal. No need to drill into or beyond the metal. As a final step, I expanded the holes in the metal Arca adapter to 7/64ths inch using that sized drill bit. (1/64th inch larger than 3/32nd inch.)

Once the holes were drilled, it was an easy matter to screw in the 8 screws.

Works great.


I happened to get the Arca adapter as part of a separate purchase, so I had that on hand. This adapter sells for $179 at B&H. I bought the Sinar bag bellows for about $50. I'm not sure how much the Sinar binocular attachment (4th photo) typically sells for. I'm thinking less than $100. Maybe still not cheap for the total project, but about $300 is less than one can expect to find the Arca Swiss equivalent for sale used. I was lucky to have the Arca adapter on hand.


It was my intention to purchase a second Arca adapter and do the same with a Sinar reflex viewer that I had. After comparing the Arca adapter to the body of the Sinar reflex viewer, this appeared like it would have worked fine. As it turned out, I purchased an Arca reflex viewer on EBay, so I gave the Sinar reflex body to a friend.

Tin Can
27-Sep-2014, 18:32
Is there a mirror in there?

neil poulsen
27-Sep-2014, 21:22
No mirror. So, the image is still upside down and reversed left to right.

The only difference between this and a dark cloth is that one's not under a dark cloth. You're holding the viewer to the eyes at ground-glass height with one hand while adjusting the camera with the other. This camera has geared rise front and back, and this makes that process easier.

I've heard of people using a strap around the back of the head to hold the viewer to the eyes while adjusting the camera w/two hands. It looks like this viewer has an anchor on each side on which to fasten a strap. Sinar may have made a strap for this viewer.

Note that the viewer is on the back of the camera only as long as it takes to compose the image. Then it's removed, focus is checked with a loupe, and a film holder is inserted to expose the negative.

27-Sep-2014, 23:27
Good project if you have the components in hand or get it cheap.

Otherwise there is a regular listing of metal one on the bay for USD185 free shipping from Hong Kong. I never used one though, wonder if anyone tried it and like to give comment.