Chamonix 45N-2 and offset lens boards

[gdi]

I am getting a 45N-2 that I hope will arrive Monday and I have a question regarding Linhof offset lens boards? I have read that there may be an index mark for those (red vs white dot) but I see different configurations in photos, some appear to have an extra dot others don’t.

Is anyone familiar with the process to zero the rise to account for the offset?

[Alan Klein]

Check with Chamonix.

[Greg]

Probably five years ago, I had the lenses for my Chamonix 4x5 mounted on a some generic ("rip-off" would probably a more accurate term) Linhof style boards. The amount of off-set fell into three groups:
two or three had the standard Linhof off-set
one had more offset than the standard Linhof off-set
one had less offset than the standard Linhof off-set.
I took each of the boards and centered the hole in the lens board aligned to the center of the GG. Then put small dots on each side of the lens board to align with the dots on the front standard. Simple solution and is simply worked. I sold the Chamonix 4x5 a few years ago, so the above is from memory but should be accurate enough for you to get the idea.

[gdi]

That makes sense Greg, thanks. I think I could also just measure the height of the center of the offset hole and compare that to the height of a properly centered hole and use the difference as the rise compensation, no?

[Greg]

That makes sense Greg, thanks. I think I could also just measure the height of the center of the offset hole and compare that to the height of a properly centered hole and use the difference as the rise compensation, no?

Sounds like a much simpler solution to mine for determining and marking the offset measurement...

[ic-racer]

Whenever I want any lens centered on any view camera, I just check that the 4 crescents are the same when I peek through the cutouts. More likely than not, if I'm using a view camera, the lens won't be centered when I make the exposure.

[Alan Klein]

That makes sense Greg, thanks. I think I could also just measure the height of the center of the offset hole and compare that to the height of a properly centered hole and use the difference as the rise compensation, no?

They're pricey but available. Chamonix boards:

Continuing to design with the principles of light weight and simple function, Chamonix has developed a carbon fiber lens board, lined with black velvet on the inside in order to reduce reflection.

Currently we have Linhof type and Sinar type boards, but we can make any size lens board to suit your needs.
https://www.chamonixviewcamera.com/accessories/lensboards

[gdi]

Whenever I want any lens centered on any view camera, I just check that the 4 crescents are the same when I peek through the cutouts. More likely than not, if I'm using a view camera, the lens won't be centered when I make the exposure.

Thanks that’s a good point….

[gdi]

Just an update - I took the offset boards and measured the distance from the top of the inner molded-in centered circle (ridge) to the top of the retaining ring (a) and likewise for the bottom to bottom distance (B). Then, the equation A-B/2 gave me the vertical adjustment to reach halfway between the top and back from of the molded circle. For two boards of different Copal sizes this number was ~6mm. So I place a small dot with an enamel paint pen 6mm above the existing dot on the standard and I can adjust very quickly to compensate for the offset when zeroing the camera.

Now to see how long my paint dot lasts!