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Bryanhaas73
Tinkerer
Username: Bryanhaas73
Post Number: 1
Registered: 07-2013
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, July 12, 2013 - 09:25 am: | 
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I'm sure this has been covered in other posts because it's such a fundamental question, but...
What is the best way to find and fix a light leak in an old 35mm SLR. I have a Minolta Maxxum and the top fifth (roughly) of each exposure is blacked out. |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 285
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, July 12, 2013 - 11:47 am: |
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If the parts between frames are not exposed, then it's sticking or not completely closing shutter.
Otherwise:
Torchlight, the "bulb" setting on the shutter and a dark room are a good start. Remove the lens, make a cardboard patch big enough to cover the lens flange and make a hole for the torchlight head, use black electric tape to lightproof it (don't forget to seal the viewfinder) and in a dark room you might actually see the light leak.
If it fails, load a piece of film into the camera in a completely dark room, wind it to frame one, shoot a photo with flash (no matter the subject), advance the film five more frames without letting any light onto or into the camera, then fire a flashgun from different directions onto the camera (don't take any photo with the camera, just give powerful light blasts from all around) while keeping the lens cap ON all the time.
Remove film, develop, if it has light leaks you can now match the pattern to the position of film inside the camera - you can tell the exact position the film was in by looking at the exposed frame and moving the film 5 frames further.
Marek |
Jon_goodman
Tinkerer
Username: Jon_goodman
Post Number: 59
Registered: 05-2007
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, July 14, 2013 - 10:05 am: |
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If the top fifth of each exposure is blacked out, that doesn't sound like a light leak. Are you taking pictures inside with a flash? At what shutter speed?
Jon |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 286
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, July 14, 2013 - 12:09 pm: |
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I assumed that "blacked out" is the negative.
If it's the positive (print) picture, I second Jon: it's hardly a light leak...
Marek |
Rick_oleson
Tinkerer
Username: Rick_oleson
Post Number: 1333
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, July 14, 2013 - 01:32 pm: |
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Quick gut check:
- Is the "blacked out" area clear or black on the film negative? If clear, it is not a light leak.
- If black: Is the area outside the negative frame - between frames, and out in the sprocket hole area - also black, or is the blacked out area occurring only within the negative frame? If the latter, the light is coming THROUGH the shutter, not around the edges of the back. |
Bryanhaas73
Tinkerer
Username: Bryanhaas73
Post Number: 2
Registered: 07-2013
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, August 15, 2013 - 03:20 pm: |
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Sorry it's taken so long for me to get back to this, and I thank you for all your feedback and comments. I need to dig out the negatives to be able to answer all your questions. If I remember correctly, the area between the frames on the negative is also affected. I need to check to see if the area around the sprocket holes is affected. The prints are darkened. I won't be so long this time. Promise. |
Bryanhaas73
Tinkerer
Username: Bryanhaas73
Post Number: 3
Registered: 07-2013
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, August 15, 2013 - 03:27 pm: |
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It's the shutter. The negative is clear. The edge is fuzzy and slightly sloping. |
Wermworm
Tinkerer
Username: Wermworm
Post Number: 3
Registered: 08-2013
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, August 17, 2013 - 08:44 am: |
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If you could post an example it would help a lot. |
Bryanhaas73
Tinkerer
Username: Bryanhaas73
Post Number: 4
Registered: 07-2013
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 20, 2013 - 02:57 pm: |
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Please see attached pdf for a scan of a print and negatives. Never mind. It won't let me post it as the scan is more than 100kB. Any other suggestions? |
M_currie
Tinkerer
Username: M_currie
Post Number: 307
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 20, 2013 - 05:21 pm: |
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Does your Maxxum allow you to operate the shutter with the back open? I don't know how this particular machine works, but many old SLR's will let you check the shutter while looking through the camera.
If it does, take the lens off, open the back, and fire the shutter at various speeds while looking through at a foot or two distance. A hanging shutter will immediately show up. If the shutter is working right, you will see the whole area (persistence of vision works for you here). If the shutter is hanging up, a part of the area will stay dark. Try at different speeds, and you will soon see if the shutter is misbhehaving only at slower speeds or only at higher, or both. At slower speeds, the entire window opens, remains so, then closes. At higher (above X sync) speeds, a slit passes over the window, and there is never a time when it is all open.
Maxxums have had some problems, but my recollection is that the dreaded "aperture base plate" problem, which can not be readily fixed, shows up in a different way from shutter issues. |
