fump
30-Dec-2018, 12:00
I recently picked up my first LF camera, the aforementioned Arca B, and a couple lenses: a Fujinon S 150/5.6 and a Fujinon S 250/6.7. I've been working in 35mm and MF for about 18 years now. This is my first experience, outside of pinholes, with sheet film.
Now that you have some background the problem: every frame I've shot with the back both vertical and horizontal has, at the darkslide removal end of the frame, a strip of drastically underexposed film. The image continues, it's just about 3 stops less exposed than the film right next to it. On some sheets there's an overexposed strip at the other end. I can't find any correlation between movements (doesn't matter if everything is carefully zeroed or if I went nuts with movements), lens (it happens with all of them), film holder (it's on every sheet I expose), or anything else.
I've looked fairly carefully through the front standard without a lensboard on and a developed sheet of film and I can't see any reason why this would happen. I've looked at the ground glass pretty carefully with a loupe and a pretty tight hood and that hasn't shed any light on the situation either.
I'm using a graflok 9x12 back with 4x5 holders and sheet, but it doesn't appear to infringe upon the film and that would yield an unexposed strip, not under, right?
I attached the worst example of this I have. There are minimal movements, just a bit of tilt on the rear standard to correct for the downward angle on the tripod. You can ignore the thumbprint and horrible light leak at the bottom, I rotated the back and didn't get it quite seated for this photo. Of course, I didn't notice until I was 50 miles away because it was miserably cold, wet, windy and I was rushing.
Any ideas of what to look at or why this is happening?
Now that you have some background the problem: every frame I've shot with the back both vertical and horizontal has, at the darkslide removal end of the frame, a strip of drastically underexposed film. The image continues, it's just about 3 stops less exposed than the film right next to it. On some sheets there's an overexposed strip at the other end. I can't find any correlation between movements (doesn't matter if everything is carefully zeroed or if I went nuts with movements), lens (it happens with all of them), film holder (it's on every sheet I expose), or anything else.
I've looked fairly carefully through the front standard without a lensboard on and a developed sheet of film and I can't see any reason why this would happen. I've looked at the ground glass pretty carefully with a loupe and a pretty tight hood and that hasn't shed any light on the situation either.
I'm using a graflok 9x12 back with 4x5 holders and sheet, but it doesn't appear to infringe upon the film and that would yield an unexposed strip, not under, right?
I attached the worst example of this I have. There are minimal movements, just a bit of tilt on the rear standard to correct for the downward angle on the tripod. You can ignore the thumbprint and horrible light leak at the bottom, I rotated the back and didn't get it quite seated for this photo. Of course, I didn't notice until I was 50 miles away because it was miserably cold, wet, windy and I was rushing.
Any ideas of what to look at or why this is happening?