View Full Version : More 12X20 heartaches / headaches!
09-23-2006, 02:24 PM
Thanks for the thoughtful words. I have 2 holders. They are newer Hoffman holders from the mid '60's is my best guess. I will have to set the whole system up in bright sun and stick my head in from all directions to try to see where the leaks are. Wondering if contact cementing some black felt cloth on the surfaces at the rear where the film holders contact the body would be counterproductive.
One thing I'm positive about. Once you leave 11X14 the problems seem to mount by magnitudes and I'm starting to wonder about diminishing returns. 8X10 just seems so easy!
I check for light leaks by putting a fairly bright light inside the camera. Close off the opening aftrer the light is in and insert a holder. Extend the bellows. Now turn off the light and walk all around the camera from front to back looking for light, Look also all around the side of the film holders.
If the fogging is overall it is probably some kind of bellows leak, or perhpas a leak near the lensboard. More localized fogging could be from the filmholder, or fit of the holder in the camera. However, Hoffman holders have a good reputation so chances are that it is the camera.
09-23-2006, 02:52 PM
Bad luck Jim sounds an expensive problem to solve, in materials testing for the fault.
Why don't you test the darkslides / film holders with B&W paper, and a second thought is do the same with the camera. You could make a very rough & ready cardboard liner that fit inside the camera, and attach B&W paer on the outside, (4 sides), and at the film holder end With a film holder in the back and the shutter closed just leave outside for an hour or so. Process the paper & you'll know exactly where to look for the light leaks.
09-23-2006, 04:24 PM
Jim, if you had to drive the length of Nevada 6 from Utah to Tonopah only to develop fogged 12x20 film as a souvenier of the trip, I can certainly understand your discouragement! Good luck in finding the gremlin that caused the problem!
09-23-2006, 04:41 PM
Thats why I always work with 2 different cameras if possibel!
In my case only a 4x5 and 8x10 but if something would be with my 8x10 I still have some shoots in 4x5 and visa versa!
But hope all gets to a good end for you Jim!
09-23-2006, 04:48 PM
All I can say -- from my own experience -- is welcome to the club.
If I had $5 for each sheet of film I have screwed up in 12x20... well, I'd have a lot of new film.
Tif and I would like you to come up again sometime, so you may have another chance at those places. Personally, I think they get better looking each year.
09-23-2006, 05:21 PM
Jim. before you run amok with felt and glue, look carefully at your felt. I make this suggestion because I have a little project for which felt looked like an easy way to make some light seals. So I went to a crafts store and bought some black felt to see how it would work. It isn't opaque enough.
09-23-2006, 05:57 PM
Jim, Ill reiterate what has been said prior already, I had similiar problems with my 717 when I first started...
I remedied it with a lot of trial and error and many sheets of cut down 16x20 silver paper to test.
One thing that made a huge difference was I took a really bright flash light put it inside the fully extended camera turned all the lights off in the darkroom and stayed in there about 20mins, my eyes adjusted and after that I noticed at least 30 light leaks. Everything from pinholes to full seams of slight amounts of light. I did do what you suggested with some self adhesive felt lining where the filmholder rests against the camera back when inserted and that made a big difference when sealing up the connection between holder and back. The biggest difference was taking the time in the dark to wait 20mins and let my eyes adjust and so many more were visible.
good luck sealing it up ... and if you get "tired" of it, send me an email. Im always still interested in taking that 1220 off your hands :)
09-23-2006, 06:56 PM
OHHH Jim, tif, and Robert I just hit the motherlode of some old pioneer buildings not on the main drag of a town down here. It's all in a town called fondly by the locals as Escapoop. Or translated Escalante. I'm going over this coming weekend to check it all out. There is also a small arts festival at the same time. Now if it doesn't snow on me three weekends in a row, I will be fine. So Jim if you have a hankering come on over. You can park, and I promise to not drive to radically. Robert and Tif if you come down, make sure Robert's GPS system is working. I can't beleive what I saw in some ink drawings at the Cedar Arts Festival. They guy promised to show me the places personally. Junkage, pronounced younkage for those who don't speak Danish, galore just a short drive from me. I can't believe I haven't seen this before. Guess I was too busy dating the first time I went to Escapoop back in the late 70's
09-24-2006, 07:25 AM
I will have to set the whole system up in bright sun and stick my head in from all directions
Just don't get stuck! :)