Linhof focusing problemgreenspun.com : LUSENET : Large format photography : One Thread
Hi all, I recently acquired an old Linhof 5x7 Tech III (I think it's a III: serial no. 25354). Packaged with the camera is an older Schneider/Linhof 180mm Symmar S, which I think is a single-coated lens. I've not shot any film yet, but I noticed that I can't get a sharply focussed image on the ground glass. I made sure that the camera is zeroed out on all the movements, but I still can't get a sharp image on the glass (checked with a loupe). I noticed that the lens has some sort of metal washer or spacer stacked with it on the board. Could this somehow be affecting the focus? There's no evidence of this Linhof ever having any rangefinder mechanism on it. Could the back be out of alignment? I'm stumped.
-- Ben Calwell (firstname.lastname@example.org), March 16, 2002
Did you own another LF camera (before)? is(was) the image on that groundglass better? I personally find that images on the groundglass are never tack sharp, but after exposing a sheet, all is ok. It's the matt surface of the glass that causes the unsharpness.
Is the image on the groundglass equally unsharp or does it restrict to a specific area?
A washer between the lens and lensboard is of no importance to focussing: but a washer between fontelement-shutter-backelement is important as the two elements must be spaced correctly.
The best way the check focus is to expose a few sheets.
-- Huib Smeets (email@example.com), March 16, 2002.
Never mind, my friends, I figured out what is wrong. I forgot to adjust the focus on my loupe for my eyeglasses! Once I did that, everything came into nice focus on the groundglass. What a dummy I am!
-- Ben Calwell (firstname.lastname@example.org), March 16, 2002.
I don't think that what you did is at all dumb. In fact, it's the reason that I've been considering buying another loupe, even though I already have a Schneider 8x.
-- Matthew Runde (email@example.com), March 16, 2002.
Thanks, you gave me a great chuckle! I know exactly where you are coming from....
-- Douglas Gould (firstname.lastname@example.org), March 16, 2002.
Throw the loupes away!!!
Go to the drug store or super market and buy yourself a pair of "reading glasses" diopter 3.5 or 4...Then you have both hands free to operate your camera and hang on to your cloth...
-- Per Volquartz (email@example.com), March 16, 2002.
Hellow Ben: "Throw your loupes away" ....NOOOOO!, well, maybe. High diopter reading glasses of the drugstore kind are OK for seeing the GG closer, povided you do not need a prescription. If you do, get your optometrist to make you the proper thing, it can make a great difference. Yes, 3.5 diopter is about OK. That magnification, for me anyway, comes well short of that needed to get precise focus. Quite obviously, the 4X5 field of view these 3.5D glasses provide, you will never see the detail that a 10X loupe does, with a very small field of view can. With my Silvestry 10X I now get perfect focus, better than before with a 6X loupe. If your loupe is less than 6X yes, do throw it away! Have a good view!
-- Julio Fernandez (firstname.lastname@example.org), March 17, 2002.