Pieter
21-Apr-2020, 18:40
Not really directly about LF, but I posted this on Photrio and I'm want to see what this forum might turn up.
Upon making some 11x14 prints of a scene that has a pretty flat sky, I discovered that one side--one corner especially--is darker (that is the print is lighter) by 1/2 stop or more. This is in comparison to an 8x10 print I made earlier in the week.
Let me explain a couple of things. The original is 2-1/4 square and the 8x10 was made with a 135mm lens, as I like having ample room to dodge & burn between the head and easel. The 11x14 was made with a 90mm lens. Condensor and bellows were adjusted appropriately for each lens. I thought it might be an issue with the lens, so I tried a 105 that I have. Same problem. I then reverted to the original 135 and the hot area no longer showed up on the print, it printed like the 8x10.
Another twist, and I suspect the culprit, is I use a small, halogen bulb instead of the oem one. It gives me a crisper print, sort of part-way to a point light source. I think it might not be perfectly centered in the lamp housing, but I wonder if there is a relatively easy method to check it and line it up.
Thanks in advance for your help and advice.
Upon making some 11x14 prints of a scene that has a pretty flat sky, I discovered that one side--one corner especially--is darker (that is the print is lighter) by 1/2 stop or more. This is in comparison to an 8x10 print I made earlier in the week.
Let me explain a couple of things. The original is 2-1/4 square and the 8x10 was made with a 135mm lens, as I like having ample room to dodge & burn between the head and easel. The 11x14 was made with a 90mm lens. Condensor and bellows were adjusted appropriately for each lens. I thought it might be an issue with the lens, so I tried a 105 that I have. Same problem. I then reverted to the original 135 and the hot area no longer showed up on the print, it printed like the 8x10.
Another twist, and I suspect the culprit, is I use a small, halogen bulb instead of the oem one. It gives me a crisper print, sort of part-way to a point light source. I think it might not be perfectly centered in the lamp housing, but I wonder if there is a relatively easy method to check it and line it up.
Thanks in advance for your help and advice.