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Leaking 1920s shutter
I've just tracked down a light leak in a 1920s Zeiss Ikon Trona 212 to, I think, the shutter blades.
With the darkslide half pulled out, left for about a minute without opening the shutter, then slide pushed back in, there is a clear but partial image in the centre of the paper negative. With the back and film holder out of the camera and looking into the back towards the lens, I can see a faint circle of light that expands and contracts when the aperture is adjusted.
As far as I can see, the shutter blades are closing completely, but it looks like some light is getting past them even when they are closed - maybe they are not resting flat against each other?
The lens is a Carl Zeiss Jena Tessar 13,5cm f/4.5, with a Compur shutter (speeds 1s-1/200s, B, T). Is anyone here familiar with these lenses? The camera has great sentimental value so I would really like to get it working, so would be prepared to pay for the problem to be fixed, if anyone could recommend a repairer in the UK.
Thanks,
Ian
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I have the same shutter & lens here in Turkey on one of my Patent Etui.
Assuming you have a Dial-set Compur unscrew the front lens cell, put the shutter on Z/T and gently press the shutter very gently and slowlyand watch the blades open, it should be a very even 3 cornered star shape taht opens. It's more likely to be a pinhole in the bellows.
A later rim-set Compur will work the same on T, just checked my other Tessar. If they are opening and closing properly they shouldn't leak light, if one blade is lazy you'll see it's out of balance.
Ian
 Originally Posted by EASmithV
*edit* Apparently I need to read more often before I post >.<
Last edited by Ian Grant; 08-29-2009 at 02:05 PM. Click to view previous post history.
Reason: It's called telepathy :D
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Perhaps you have a pinhole in your bellows, and you are getting a pinhole image?
*edit* Apparently I need to read more often before I post >.<
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If the shutter's not closing all the way it is a pinhole.
Shine a light through the lens with the shutter closed, if it's open you will see it. You may need to darken the room a little bit too.
A motorcyclist is the only one who understands why a dog rides with it's head out the window.
"I had an idea once, it died of loneliness"--George
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I think I may have been wrong about the shutter. The blades are opening and closing smoothly and evenly, and when closing keep moving after I can no longer see a dot of light in the centre so there is definite overlap. The circle of light I could see yesterday is possibly the reflection from the back of the shutter blades of the faint light coming in under my improvised dark cloth.
Now the paper negative is fully dry and I've had a more detailed look the image has a pinhole look to it. Even in a darkened room, looking into the camera back and shining a torch around the lens and bellows I can't see a leak. I guess the way forward may be to put it back on a tripod outdoors and repeat my first test on several sheets of paper while keeping different parts of the bellows covered with something that's defintely light proof to track down the problem to one area.
Thanks,
Ian
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I may have some Plate holders and a roll film back that fit your Zeiss, they don't fit any of my 5 9x12"s. Also I still have that Kodak Safelight for you so when I'm next in the UK I'll get in touch.
Ian
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Thanks Ian, very much appreciated. The camera only had a single plate holder with it, plus a pack film holder. I've found a source of quarter plate film, so if I can get this light leak fixed, should be all set. The camera was bought new by my grandfather, and well used until he upgraded to a Super Ikonta. We have boxes of plates which I'm slowly sorting through and contact printing.
Ian
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There are two holes in the bellows corners right at the upper back, only visible by looking almost inside the case from the front. I had to put my torch right up close, and look up from the bottom to see the light coming through. Taped the corners with small pieces of black PVC, and paper negatives are now clear, even leaving the camera out in the sun for a few minutes with the darkslide open. Good enough to make a decent contact print on a postcard for my uncle who gave me the camera.
There's a box of film on the way - looking forward to making some enlargeable negatives 
Ian
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