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View Full Version : Film Holder Light Leak - Suggestions Please



David Karp
1-Jun-2008, 22:30
I have used my whole plate Improved Seneca camera and film holders that I purchased from Jim Galli with no problems. It is a nice camera and the holders work perfectly.

After buying the camera, I picked up some additional Eastman WP film holders on E-Bay. They looked good, but it turns out one of them has a light leak. It looks like the light trap is bad. Of course, I never labeled the holders (duh), so now I have to test all of my holders, because I cannot identify the ones I purchased from Jim. Oh well.

My plan is to somewhat follow the procedure that Michael Mutmansky followed in his ULF film holder test in a recent issue of View Camera. He performed a different test on each side:

Side One: pull the darkslide with the holder in the camera, and the camera turned so that the darkslide slot faces the sun. Leave the holder in that position for five minutes.

Side Two: Leave the holder in the sun, with the other side up, in direct sunlight for 30 minutes, and cloudy light for another 45 minutes.

WP film is expensive, so I would rather not waste film on testing. I was thinking of using enlarging paper for the tests. Also, before reading this article I planned to do only the Side One test. Do you see any reason to perform the Side Two test described above?

Any other suggestions?

Thanks.

CP Goerz
1-Jun-2008, 23:03
I bought some old RC paper from Freestyle just for this purpose..a cheap and fast alternative to film for testing, it'll work just fine.

CP Goerz

robert fallis
1-Jun-2008, 23:06
yes use paper it's cheaper, and I think I would do both tests

bob

Brian Ellis
2-Jun-2008, 06:45
Paper will work but won't you need to significantly increase the times to perform the equivalent of a test using film? When making paper negatives paper is usually rated at about 5, obviously much lower than even the slowest film. And whether you use film or paper, I'd do both tests. If you're going to bother testing at all, why go only half-way?

BradS
2-Jun-2008, 16:15
Have you subjected the film holders to a careful visual inspection? Usually, light leaks through the darkslide slot can be seen with the naked eye - if carefully inspected. That's been my experience anyway.

Check that none of the film holders is warped too.

David Karp
2-Jun-2008, 20:20
Thanks guys.

I will do both tests. My plan is to do both tests for each side.

I appreciate the input.

John Kasaian
2-Jun-2008, 20:48
The holders you bought from Jim Galli can probably be identified by how they smell--- they'd be the ones that smell like Tonopah, Nevada sage brush :D (Sorry, Jim---I couldn't resist! :D)

David Karp
2-Jun-2008, 21:06
Now all of my holders smell like a burnt Universal Studios!

Donald Miller
2-Jun-2008, 23:03
I have tested film holders without using either film or paper...by inserting the film holder then removing the darkslide and the lens panel and directing light from the interior of the camera all around the rear of the camera in a darkened room. If light gets in then it will surely come out.

Mike Castles
3-Jun-2008, 05:09
I have tested film holders without using either film or paper...by inserting the film holder then removing the darkslide and the lens panel and directing light from the interior of the camera all around the rear of the camera in a darkened room. If light gets in then it will surely come out.

Interesting Donald, makes perfect sense. Will give it a try next time I need to check some holders. Saves on both paper and film and is much like checking the bellows (which seems you could check them at the same time by replacing the lens board.

Thanks

seawolf66
3-Jun-2008, 20:48
David: I picked up a three tooth brush like set of three, one is made of brass , one is made of stainless steel and the last one if stiff plastic bristles which I use to clean out the felt groves from dust or dirt that may be trapped there: Just a thought ; Thats all

Jim Galli
4-Jun-2008, 07:10
Oh dear. Did Universal Studios burn up? Are the rubber dummies that Weston photographed finally dead??

My method with no film at all is to set the camera on a tripod out in bright sun, make a lensboard with only a hole for my eye, insert film holder, remove dark slide, and do a 360 degree dance with the sun finding every possible angle while I'm looking through the hole in front.

I wonder what my neighbors think? Uh, no i don't.

David Karp
4-Jun-2008, 08:16
Hi Jim,

Yeah, they had a big fire: http://www.latimes.com/news/local/valley/la-me-studiofire3-2008jun03,0,928009.story

Most of it is fine.

I have a board that will work just fine for your method. Maybe I can find an obvious problem that way.

Thanks.

IanG
5-Jun-2008, 03:20
David, I had unexplainable light leaks in two or three darkslides (film holders). Unfortunately Jim & Donalds methods wouldn't have shown where the problem really was.

It wasn't the actual film holder itself or the light seal it was the sheath, in the UK we use slightly different terminology, a darkslide is a film holder, what you in the US call the darkslide is the sheath :D

There were cracks in the sheaths, some almost invisible, these let light in but only in extremely bright sunlight. In fact I managed to repair them all with Super-glue and black nail polish, and even in the harsh sunlight here in Turkey they are now fully light-tight.

Ian