uneven exposure

[steve hartsfield]

My 4x5 negatives exhibit a 0.5 inch over exposed strip down the right side (looking from the ground glass side) and the film is loaded horizontally (haven't tried this with the film loaded vertically). It appears to be a light leak resulting in about 2 zones exposure. I do tray processing and I have tried new boxes of film.

My equipment is a Wista cherrywood (1984), Nikkor 120 and Schneider 210 lenses. I have taken the back off, covered the camera and looked through it with a lens mounted. I can detect no light leak with the shutter closed. Do the holders let light leak past the slide entrance as they age? This started about 3 years after I bought the camera and holders. :(

[Gem Singer]

"Do the holders let light leak past the slide entrance as they age?"

They certainly do!

The light traps on older film holders are notorious for leaking. Use your dark cloth to cover the film holder when you pull the dark slide. Better yet, get newer film holders and test them for leaks.

[Robert Oliver]

go into a dark, dark room and put a flash light inside of the camera. I would start by taking off the lens board and inserting your flashlight in through the lens board opening. Make sure your sheet film holders are loaded into the camera. Wait for your eyes to get used to the dark and any light leaks should be readily apparent. Also try it with the dark slides removed.

Is this only happening with one holder or with multiple film holders. If i had to guess, I would think that maybe your film holders are not getting inserted all of the way or something is keeping them from seating properly. I wouldn't think that all of your holders would develop the same leak at the same time, but yes the felt can deteriorate and cause light leaks. Just not all at the same time in my opinion. Light leaks from the dark slide felt is usually spotty and would usually not fog the entire edge of the film, unless the entire strip of felt was taken out of every holder.

Good luck.

[steve hartsfield]

Thank you, I will give it a try in the dark room and report back in a couple of days.