Light streak coming from the darkslide opening, while getting blasted by direct sunlight. Adox CHS 25 in Xtol 1+3 |
The second occasion was much more subtle and I had no idea anything was going wrong until I processed the film. I had a light leak. And it wasn't the kind I was used to seeing. When you shoot medium format, you have to be a bit more careful with exposed rolls than you would with 35mm. The only thing keeping light from striking the edges of the roll is the film's close tolerance to the ends of the spool. Sometimes the spool is warped (or was just a piece of shit to begin with) or the film is wound on slightly askew leaving a gap where you'll get a bloom along the edge of the film. The other is common occurrence is when the roll has been exposed to ridiculously bright light and it will actually burn through the backing paper. This is easy to spot because it burns in the frame numbers that are printed on the backing paper.
Light streak coming from darkslide opening, while facing away from the sun. Adox CHS 25 in Xtol 1+3 |
However, the light streaks I encountered were different. They were all happening at the same place and they were mainly presenting as a line that made its way nearly across the entire frame. The most telling indicator of the root cause was that they were all coming from the side of the film back where the darkslide is inserted (the side with the two V-shaped notches).
Thankfully, this is as easy as a Hasselblad repair can get. Where the darkslide is inserted there is a light trap to keep it sealed up when the slide is removed. It's nothing more than a specially shaped piece of foam folded in the middle of a piece of foil. I hope that it's made from an exotic material, or that it's from the future, or something to help justify its $18 price tag. At least the folks at their New Jersey repair center were super helpful on the phone and got the parts shipped out to me the same day.
Nine screws hold the faceplate on the A12 back. |
Replacing the light trap is very straight forward. There are nine screws that hold the faceplate of the film back on. Remove those and pop the faceplate off. Remove the old seal, which is mercifully not glued in place and replace with the new foam and foil. The shape of the cutout makes it pretty obvious how it all gets situated in there. I also took the opportunity to clean the piece of fabric on the faceplate that was full of 30 years of dust and gunk. I used the darkslide to hold the new seal in place while I reattached the faceplate. Done.
Thankfully the roll I was shooting was not super important. It was more to try out Adox's CHS 25 film than anything else, so I'm glad I found out about the problem before I ruined a roll that I would have seriously regretted. My point is that I bought both of my film backs used, and they are both about 30 years old. There was no service record for them, so these could have been the original seals. If I had the forethought to check them out when I first got them, I probably could have avoided messing up this roll of film.
A12 with faceplate removed. Light trap on right side. Note black fabric strip on faceplate that could probably also use some attention. |
Ruptured foil on the light trap. The seals normally fail when the foam disintegrates. Mine wanted to go out in style, I suppose. |