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AtlantaTerry
28-May-2016, 21:30
I just purchased a Chamonix 045F1 camera which uses Linhof lens boards. Is there any reason I would want a Linhof lens board where the hole is not centered?

B.S.Kumar
28-May-2016, 22:04
If the hole in the lensboard is offset down, you get an automatic "fall" of 7~8mm. Usually field cameras do not have fall, unless you tilt the back backwards and drop the bed, then make the lens parallel to the back.

Kumar

AtlantaTerry
29-May-2016, 00:59
If the hole in the lensboard is offset down, you get an automatic "fall" of 7~8mm. Usually field cameras do not have fall, unless you tilt the back backwards and drop the bed, then make the lens parallel to the back.

Kumar

I was thinking more about "rise" for architectural work. I suppose "fall" might be useful for Scheimpflug work so when you also tipped the lens forward, the light would have a better chance of covering the media.

But it would seem to me to have a lens installed on an offset lensboard on the off chance that "rise" or "fall" might be needed would, in the long run, be a hassle.

Bob Salomon
29-May-2016, 07:35
Linhof boards are not centered. Non Linhof manufactured boards may be centered.

AtlantaTerry
29-May-2016, 22:41
Linhof boards are not centered. Non Linhof manufactured boards may be centered.

What about Chamonix lens boards? Those are supposed to be Linhof style. Are the holes in the Chamonix carbon fiber lens boards centered?

Also, why did Linhof see the need to drill the hole off-center? Was it as mentioned - for "fall" to be built-in?

Thanks,
Terry

Oren Grad
29-May-2016, 23:24
Also, why did Linhof see the need to drill the hole off-center? Was it as mentioned - for "fall" to be built-in?

Terry - there's no fall built in to a Technika. With a Linhof-standard (i.e., offset downward) board mounted and the front standard in its default (lowest) position, the lens is vertically centered relative to the back. From that position, only rise is available directly on the front standard. If you want fall, you need to either invert the camera (which turns rise into fall) or drop the focusing bed and tilt the front standard back to restore parallelism.

If you use a centered board on a Technika, the lens will actually be shifted upward relative to the back, and there won't be an easy way to center it.

Many wooden field cameras have a decent amount of both rise and fall available on the front standard. If that's the case with yours, you can center a lens mounted on either type of board and can choose your boards based on which direction you'd prefer to have more residual movement available when the lens is centered.

Doremus Scudder
30-May-2016, 00:41
From the photographs on the website, it looks to me as if the Chamonix is designed for the Linhof-style offset lensboards. That would mean that the lens in "zero" position would be centered on the film with such a board. A center-drilled board would place the optical center a bit higher on the film. Maybe Hugo or a Chamonix owner can confirm this. Normally, you would want the lens centered on the film when the camera was set as its "zero" position.

Now, whether you want the center-drilled board is another issue. I have Wista cameras designed to take offset Linhof boards. I've mounted the lenses I use most for outdoor architectural work (90mm & 135mm) on center-drilled boards so that I can squeeze that little bit extra rise out of them. This keeps me from having to use the "point up and tilt parallel" trick as often and is a time saver. However, when I want "zero" position with these lenses, I have to use front fall to achieve it.

If the Chamonix has enough fall to center a lens on a center-drilled board, and you tend to use rise quite often but (like me) almost never use fall, then you might consider getting a center-drilled board to give you a bit more rise. I assume the Chamonix has enough fall to correctly position a center-drilled lensboard.

First thing, though, is to confirm for which type of board your camera was designed and then decide, based on that and your shooting habits, if a center-drilled board would be useful.

Best,

Doremus

Bob Salomon
30-May-2016, 07:39
What about Chamonix lens boards? Those are supposed to be Linhof style. Are the holes in the Chamonix carbon fiber lens boards centered?

Also, why did Linhof see the need to drill the hole off-center? Was it as mentioned - for "fall" to be built-in?

Thanks,
Terry

As I have stated here many times before. The Linhof holes are placed where they are so the lens will be centered on the ground glass of the Linhof camera.

Greg
30-May-2016, 07:55
Are the holes in the Chamonix carbon fiber lens boards centered?

Hole in OEM Chamonix boards is off center. Beware of no brand name boards that have the hole centered... the round dimple? (light baffle) on the rear of the board is also centered and will not fit in the 4x5 Chamonix front standard. Once bought 2 cheap and had to grind off the rear dimple and paint it flat black but even then the board was a bit thinner and I had to tape the top and bottom so it wouldn't wobble in the front standard. FYI boards were in new condition but not returnable so had to make the best of the situation.

Argentum
30-May-2016, 08:13
does the camera have a centering mark/detent on the front standard. If so then position it at the centering mark and visually check if lens axis is centered on GG. If it is then all is good and nothing to be concerened about.
If lens axis is lower than center of GG then all is not lost. It just means you have to put a little rise in to center it. You will still have approx 38mm of rise available which will be plenty anyway. So I don't think its a problem at all whether you are using an off center lens board or not. It might be slightly annoying if the front standard does have a centering mark and lens is not centered on it but its nothing that causes the camera not to function. You could easily make a secondary mark(tape) for off centered lens panels if necessary.

Jac@stafford.net
30-May-2016, 08:44
I just purchased a Chamonix 045F1 camera which uses Linhof lens boards. Is there any reason I would want a Linhof lens board where the hole is not centered?

Getting to the original question, the short answer is using a Linhof technika board on the Chamonix 045F1 is silly. Linhof is more expensive and the offset is not required on the Chamonix.

Argentum
30-May-2016, 09:32
methinks looking at the photographs of that camera that the fitting is designed for linhof technika lens boards as the hole is offset downwards by the look of it.
So if you have a linhof board it should be correct for your camera.
Note that some older linhof boards are not the same as current linhofs boards. I don't know when the change was made but it was quite a long time ago.

Why not get the chamonix made boards which will obviously be correct.

Linhof boards have a big circle that sits proud of the back of the board and will fit into the hole on your chamonix. A centered board which has that circle may not fit into your cameras hole. Not too sure about that but why take the risk when the thing is designed for linhof style boards with the fitting lugs etc.

Bob Salomon
30-May-2016, 10:16
methinks looking at the photographs of that camera that the fitting is designed for linhof technika lens boards as the hole is offset downwards by the look of it.
So if you have a linhof board it should be correct for your camera.
Note that some older linhof boards are not the same as current linhofs boards. I don't know when the change was made but it was quite a long time ago.

Why not get the chamonix made boards which will obviously be correct.

Linhof boards have a big circle that sits proud of the back of the board and will fit into the hole on your chamonix. A centered board which has that circle may not fit into your cameras hole. Not too sure about that but why take the risk when the thing is designed for linhof style boards with the fitting lugs etc.

Technika III boards are a different size then boards made for the IV and later cameras. A few years ago Linhof made some changes to their cameras and boards to eliminate any loose play in the board's fit. That made the tolerances so tight that older boards would not always mount on newer cameras unless a layer of paint on each long side of the board was removed with the edge of a butter knive.