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Matthew Padden
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, July 20, 2004 - 11:25 am: | 
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Hi,
Just got back a contact sheet of colour film that I took with my Zenit EM. At several points along the film, there are coloured blotches.
The blotches are either red or blue/white (like a gas flame), and they are all along the lower edge of the images. They vary in intensity. Some of them extend across the sprocket holes and onto the outer edge of the film.
Many occur at the same position in each frame. However, two are centred on borders between successive frames.
Normally I'd take such blotches to be light leakage from somewhere around the prism, but the fact that they are strikingly coloured makes me wonder if they are process-related.
Any advice appreciated!
Best regards,
Matt
Glasgow, UK |
Jon Goodman
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, July 20, 2004 - 12:01 pm: |
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Hi, Matt. They could be process related, however I'm going to suspect a light leak at this point. Because the damage is at the bottom of the images, we know light is striking the film at the top part of the camera somewhere. Zenits are famous for leaking here:
http://www.members.aol.com/jgood21967/zenitleak
but in your case, I don't think this is happening.
Leaks at the upper and/or lower film door slots are not uncommon. These cameras were originally sealed with a cord-like twine material. This is good only as long as it is still intact. Often it has snagged the film door and has been pulled out and thrown away by some previous owner. The hinge end seal was a cloth affair, and it may leak (although this is not a common thing). Further to all this, in very bright light, light can run in through the meter needle window and be caught by the edge of the pentaprism which extends past the viewfinder window.
The fact the damage is at the same place, extending to the edge of the film and colored actually makes me think light is striking the film from behind. At least, this has been my experience. Because of this, I'd start searching at the film door.
Jon |
Matthew Padden
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, July 21, 2004 - 01:44 am: |
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Hi Jon,
Thanks for your thoughts. I made a quick check of the door seals last night, and they seem to be in good order. I did in fact replace them a few months back following earlier discussions on the message board.
I'll make a more thorough investigation tonight. I'm wondering if light is getting in through the light-meter window, or whether there is a gap underneath the viewfinder eyepiece that defeats the door seal. Failing that it may be a gap around the mirror.
I'll let you know my findings later tonight.
Best regards,
Matt |
Matthew Padden
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, July 21, 2004 - 02:23 pm: |
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Hi Jon,
I made some more intensive investigations tonight. Here's what I found.
The upper and lower door seals seem to be good, as do the hinge and latch seals. No dents or uneven edges etc along the metal door edge, or along the film rail guides or the pressure plate.
However, if I shine a torch into the front of the camera, in 'fired' state and with the door open, light can be seen spilling out below the viewfinder eyepiece as well as through the eyepiece itself. There is a gap in the Zenit body just here, so that directly under the eyepiece there is nothing above the door seal material.
So what I am wondering is, the light is breaching the door seal at this weak point and running down across the back of the film. The door seal itself shows no signs of weakness (it's an Interslice one that I fitted a few months ago), but the light source in this case is impinging directly onto it at a point where it's not as well secured as elsewhere along its length. On several of the frames the rough position of the leak corresponds with the sides of the bodywork gap under the eyepiece, which strengthens my suspicions.
In an alternative scenario, if I fire and lock open the shutter on 'B' speed, and then shine torchlight into the eyepiece, I can see light leaking around the edges of the mirror. However, I'm dubious about this being the cause. The coloured leaks sometimes occur at frame boundaries, suggesting they are happening independently of the shutter being fired.
I also found that torchlight shone into the eyepiece can be clearly seen from the lightmeter window, as you mentioned. Thereby the reverse path is also possible, leaking through onto the film back via the gap under the eyepiece.
So my intentions are to close the gap under the eyepiece, and also shroud off the lightmeter window from the rest of the camera's upper body.
Does that make sense?
Best regards,
Matt |
Jon Goodman
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, July 21, 2004 - 02:36 pm: |
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Hi, Matt.
It makes good sense. If you look at the tri-picture frame I attached above, you'll see the corner of a piece of light seal material heading back to the viewfinder. In that camera, I had to seal that area (under the viewfinder) to stop it from feeding light past the seal in bright conditions. Also, the pentaprism corner will pick up light from the meter window, as you noticed. That generally isn't a problem, but if it is very bright, you'll get enough overspill that the pictures come out "milky" or washed out. I think the area beneath the viewfinder window may hold part of the answer in your case, though. It sounds like it, anyway. In any case, I completely agree the leak is occurring independent of the shutter.
Jon |
Matthew Padden
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, July 21, 2004 - 03:31 pm: |
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Jon, thanks as ever for the thoughts. Hopefully I'll be able to address the leak this week, although moving house may get in the way (I did finally manage to buy one after large amounts of delay!)
I've not had any milky/washed-out images so far, but I'll cure the lightmeter window leak in any case.
Best regards,
Matt |
Roxan
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 24, 2005 - 06:00 pm: |
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Is anyone aware of any camera Repair shops capable of repairing a Zenit 11? The curtain was loose and following disassembly (done carefully), the adhesive was weak.If anyone knows any contacts or sources I would deeply appreciate it |
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