PDA

View Full Version : Question about lens boards and Copal 3 shutters



StuartR
6-Jun-2019, 10:40
Hello all. I have a beautiful 300mm Fujinon CM-W that came mounted on a Linhof lens board. I am using a Chamonix 8x10 camera with a Sinar to Linhof adapter. Unfortunately there is some play in the adapter when I place the lens on the camera. Because of this, I wanted to replace the Linhof board with a Sinar one. As you can see in the picture, there is a gap between the board and the shutter. I assume this is to allow for handling the lens on the smaller board. I assumed that the board itself was built with the spacer, but when I took the board off, I saw that the retaining screw itself acts as a spacer. I want to order a new board, but I am wondering what I should get. Should I just get a flat board for a Copal 3 and use the existing spacers, or can I get a new retaining screw so that the shutter sits directly on the board like a typical lens. I think the latter would likely be preferable, as it would mean the lens was better balanced in the lens board and front standard. Right now it sticks out a bit and is rather front heavy.

By the way, the green tape is to add a bit of thickness so it sits more solidly in the adapter. This is not ideal, obviously, but it seems to help in the meantime. Also, I guess this is a Copal 3S shutter? It does not say #3, and from what I read, it is slightly different. I hope it needs just a standard Copal 3 lens board.

192136

192135

Bob Salomon
6-Jun-2019, 11:34
The 3 shutter comes with a spacer ring to prevent the back of the shutter from contacting the board which would prevent the aperture lever from moving or moving smoothly.
The small screw is provided to prevent the shutter from rotating on the board. If your board is not milled out for the screw then your shutter is not parallel to your board. In that case just remove the screw and toss it away.

StuartR
6-Jun-2019, 11:56
Thank you Bob. I do not see the screw you are referring to. I meant that the retaining ring (which I called a screw above, probably confusingly) is not a retaining ring like I am used to on smaller shutters...it is approximate 9.5mm thick and passes through the gap in the lens board, and has a small flange to keep the lensboard tight. The spacer is 6.5mm and fits perfectly between the retaining ring and lens board.
So it sounds like all this is by design for all lens boards, so if I just get a flat Sinar board for Copal 3, all should be fine?
I am attaching a picture of it all disassembled for clarification.
192140
192141

Alan9940
6-Jun-2019, 21:42
This sounds and looks like the same setup I have on a 480mm Schneider Apo-Artar that I have mounted on an 8x10 Deardorff lens board. I haven't looked specifically at the mounting for this lens in 30+ years, but based on memory the non-thread ring fits over the rear of the shutter while the threaded one is screwed down through the "spacer ring". Does this make sense? If the hole in the lens board is of proper Copal 3 size, I wouldn't think board thickness would matter. Perhaps I simply don't understand what you're asking?

pepeguitarra
6-Jun-2019, 21:51
Check to see if your board is for Copal 3S or for Copal 3. The only way to find out is measuring it. I had the same case, but I found the correct board and everything is fine.

B.S.Kumar
7-Jun-2019, 06:12
1. That's a #3 shutter.
2. If you find some play, it means the retaining ring is not seated properly.
3. To ensure that it is:
a. Take the lens off the board.
b. Remove the lens cells, the ring and the spacer from the shutter.
c. Insert the retaining ring through the board from the rear.
d. Insert the shutter into the spacer and then screw it into the retaining ring.
e. The spacer should be free to rotate until it is held firmly in place by the shutter and the board.
f. Replace the lens cells.

Kumar

StuartR
7-Jun-2019, 06:27
Thank you all. I am sorry if it was confusing. I think my biggest questions were whether the shutter should be directly against the lens board like on a 0 or 1 shutter. Bob told me that the 3 shutter is supposed to have this gap here so that it does not get in the way of the iris mechanism. I was also unsure if I should buy a standard, flat Copal 3 lens board, or one with a recessed or top hat configuration. Again, it seems like flat is the way to go for a regular camera.
Finally, the play I was referring to was not in the lens or board, but between the board and the adapter. The Chamonix Sinar to Linhof adapter has a metal flange and two metal levers that hold the Linhof board in place. Behind the board is some felt. It is here that there is slight play...the lens board seems a little too thin to be completely still here. It is a Toyo View lens board. My Ebony linhof board fits securely, so I think it is just the Toyo lens board.

Thanks for all the help and sorry for all the confusion!
Best,
Stuart

B.S.Kumar
7-Jun-2019, 06:38
Usually, there is no felt or other material behind the sliders.
Sometimes, the screws holding the sliders can be tightened to hold the board firmly.

Kumar

klw
7-Jun-2019, 10:45
Finally, the play I was referring to was not in the lens or board, but between the board and the adapter. The Chamonix Sinar to Linhof adapter has a metal flange and two metal levers that hold the Linhof board in place. Behind the board is some felt. It is here that there is slight play...the lens board seems a little too thin to be completely still here. It is a Toyo View lens board. My Ebony linhof board fits securely, so I think it is just the Toyo lens board.

Since you already have the adapter board, you could use a different (better fitting) Linhof style board (not the Toyo). I like them because they are small (= use less space in the bag).

StuartR
7-Jun-2019, 12:46
Since you already have the adapter board, you could use a different (better fitting) Linhof style board (not the Toyo). I like them because they are small (= use less space in the bag).

Yes, this is probably an option too. I have most of my lenses on Linhof boards as I use those for my 4x5, but I figured since this lens is primarily going to be used for 8x10, that perhaps it was better to just keep it native to maximize the stability. But you are right, it might be a better idea just to get a Chamonix Linhof board, as I understand their CF boards are a bit thicker than some others.

StuartR
7-Jun-2019, 13:05
P.S. I took a caliper to the lensboards I have, and the Toyo is about 1.7mm thick in the main part of the board, but uses planed metal to take it to 2mm at three points across the lens board. The Ebony board I have is simply flat, but 2mm across the whole surface, which would explain why it fits a bit better in the Chamonix adapter.

Keith Pitman
7-Jun-2019, 15:42
Look for a recent review of Linhof-type lensboards on this forum. I believe a conclusion was that Luland boards were good quality and not expensive. I believe thickness was measured also.

pepeguitarra
7-Jun-2019, 19:27
Look for a recent review of Linhof-type lensboards on this forum. I believe a conclusion was that Luland boards were good quality and not expensive. I believe thickness was measured also.

I remember the discussion, that is why I bought an adapter from 8x10 Sinar to 4x5 to use on my Intrepid 8x10. It did not work. The Lulands did not work on my Intrepid adapter 8x10 to 4x5 either.

klw
7-Jun-2019, 22:00
I remember the discussion, that is why I bought an adapter from 8x10 Sinar to 4x5 to use on my Intrepid 8x10. It did not work. The Lulands did not work on my Intrepid adapter 8x10 to 4x5 either.

Then your Adapter may be off. I bought some and do recommend them.