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Terence Falk
22-Feb-2013, 15:43
I purchased a digital depth gauge to check the ground glass in my Linhof Kardan Color 45s monorail 4x5 camera. My question is where do I rest the gauge? There is a ridge around the edge of the image area, but I dont know if that is even all the way around. I have attached photos of both the place I have been trying to read as well as an overall photo of the inside of the back of my camera. Any thoughts as to where I should rest the gauge?8996789968[ATTACH=CONFIG]89967

AJ Edmondson
22-Feb-2013, 15:55
The simplest way is to attach the gauge to a straight-edge spanning the ridge and zero it out against the ground-glass, subsequently - insert a film holder with a scrap sheet of film (without changing the zero setting) and note the readings as positive or negative deviations. I found the easiest way to do this is to drill a hole to accommodate the stem of the indicator in a piece of hardwood which has been planed/sanded to a smooth, flat surface (on the lower side since this is the side which is slid around on the ridge to note the readings at various places). Obviously, this presupposes that the ridge is uniform and smooth. Otherwise you have to resort to a "goose-neck" holder for the indicator and moving the entire back (which usually means a granite surface plate).

Bob Salomon
22-Feb-2013, 16:18
The ground surface of a gg in a Linhof camera rests on the shims in the corners that rest on the small adjustable posts. Unless someone removed a Fresnel screen from under the gg then leave everything alone or take it to a qualified service center. And I mean QUALIFIED. We have seen too many jobs ruined by photographers or unqualified service centers trying DIY adjustments.
There is a much better chance that a focus problem with the film plane lies in the film holder then with the gg adjustments.

Terence Falk
22-Feb-2013, 17:22
Bob, Can I bring it to Nippon Photoclinic?

Bob Salomon
22-Feb-2013, 17:40
Bob, Can I bring it to Nippon Photoclinic?

Should be able to. They were factory trained in Dec.