I purchased a used Gandofi Variant Level 3 a few months back, right before I began construction on my new darkroom. I ran some quick tests, found everything to be satisfactory, and ended up selling my Toyo 45AII.
A few weeks ago, after I had finished the darkroom, I started going out more with the camera. However, I found that I was getting fogged negatives. I initially though it was the Grafmatic backs, but after further testing, and careful inspection of the camera, I found that it was letting an unsettling amount of light in (well, any light not coming in through the lens would be unsettling!).
There were three light leaks:
1. Around the lens opening in the front standard, due to poor fitting lens boards. One of my lens boards was fine; the other three were way too loose. This leak was fixed by putting a ring of weather stripping around the inside of the opening, painting the opening black (it was finished wood before), and using black tape on the inside of the opening to make sure that no light would leak underneath the weather stripping. Leak covered.
2. My camera has a revolving back (Calumet/Cambo?). When a light is shone from the inside of the camera out at a very particular angle (with a grafmatic loaded), you can see light on the outside of the camera. However, going the other direction does not show any light at all, at least that I can see.
3. After further investigation of the back, it appears that Grafmatics don't work particularly well with this camera back - the springs are stretched too far to hold the back snugly in place. I thought about using the backs with just the clips (remove the glass), but I'm not confident that the clips would hold the back securely enough. After further investigation, it appears that #2 may be caused the Grafmatic's as well, due to the stress put on the revolving back.
As I test, I put all my 2-sheet film holders through a strenuous test outside in the bright sunshine, with no protection for the back. Expose a negative, rotate the back, and the camera in the sunshine. Developed all the negs - no fogging.
So, I'm back to my cut sheet film holders. I can only carry 24 sheets of film as opposed to 36, but it's still pretty tough to run through 24 sheets in a single day.
After that long narrative, has anyone else has problems with rotating backs? How about light leaks in general - had problems finding a leak?
It took me about 3 hours Friday night, and a few hours Sunday to diagnose and fix all these problems. I know, however, can rest assured that I have a light-tight camera.
I hope :-D