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  1. #1

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    7 x 17 light leaks - HELP!

    Ok, is it bellows, or light leaks? It's killing me. I have ruined 'dozens' of images with leaky corners.....It's a Phillips 7 x 17 and S & S holders...In the corners where the flaps are for my S & S holders, I am getting leaks...it's like a dark fan, about size of a quarter. It's consistent with most of my holders, except in the shade....no flare. I have tried g claron lens, dagor, artar - with lens shades, of course. .....I get the leak/flare. So, I put a flashlight in the camera, put a lens on with lens cover, inserted holder, and NO light visible in the dark, Notta, nothing. Exposures, from 15th to a second...doesn't matter. Bellows close or extended. I have had the 'issues'...

    Any one else have problems with S & S holders? I don't think it's the camera as I did not see any light when I did the test in the dark. I tried black paint in the flap, but not sure if I did it right - i.e do you need to paint the inside slot that accepts the holder. Do I need to add some tape on the flap end for extra measure? Like around the seams?

  2. #2
    John_Brewer's Avatar
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    Knowing that the two people who make those holders are passionate LF practioners I would think that they are built to the highest standards. I suppose you could have a bought a mistreated secondhand film holder, but you imply you are having problems with more than one. I would suspect the camera. Maybe you could post a print showing the fogging. Sharpness, position and angle of the fogging all help to narrow down the source of the problem.
    ~John~
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  3. #3
    resummerfield's Avatar
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    I’ll have to agree with John. If you have tried various lenses, and multiple holders, and have the flare/leak in all films (except when in the shade), I would guess you have a camera/bellows leak. The 7x17 holders have no standard, so check how the S&S holders fit the camera. Are the mating surfaces between camera back and holder flat and free of warps? Is there a good fit at the “lock tab”?
    —Eric

  4. #4

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    I have checked for leaks in the dark with light in the camera...what else can I do to check camera/holder fit? Thanks. I will try and scan and show effect. Imagine two small fans in the corners of the negative by the flap end. The insides of the holders are plain wood, on the edges, not black, could I be getting reflection off of the inside of the holder when the slide is pulled?

  5. #5
    billschwab's Avatar
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    It sounds to me like it is definitely in the way the holder fits the camera. The fact you are not seeing light in your dark test might not matter that much. Try doing a test exposure in the sun with your darkcloth draped over the camera back and see if you get a clean negative. If so it will rule-out your bellows. In my experience a bellows leak would be much less localized and more of a fogging effect.

    When seated, does the flap end of the film holder hang out from behind the sprung ground glass back? If so, maybe direct sunlight can shine on the crack between the flap and flare the corners of the film. It wouldn't take much. It also might be that the flare is coming not at the time of exposure, but when the film holder is turned to expose the film on the other side of the holder.

    Bill

  6. #6

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    If you could scan the problem and post it, it will help a lot. YOu need to talk to Sandy and ask him if you have the old style holder or the new one. The older style did have some problems with light leaks but the problem was at the light trap not at the flap. From your description it seems the holders are not seating correctly on the camera or are slightly smaller than the camera.

    Another thing you might want to make sure is that you are inserting the dark slide all the way in. With these big holders sometimes the slide feels like it has gone all the way in but many time it has not. Load a wasted film in the dark, turn the light on and check that the slide is seated all the way in.

    Place a holder in the camera and in the dark shine a flash light through the lens hole (with the bellows extended all the way out) and check if you can see light from the GG side.

    Fan like leaks are usually an indication of a small pinhole near the holder, you might want to check that the bellows is also held correctly in the back.

    Good luck.

  7. #7

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    To add what Jorge said, I had a similar situation a while back with some of my S&S holders. First step was to paint the inner portion of the flap flat black. That inproved the situation but it was still evident. Sandy has increased the receipt depth of the flap that accepts the slide and he also midified the light trap. I believe that Sandy is at the J&C conference in Toronto and when he gets back he will resolve the issue for you. Hang in there, the solution is around the corner.

    Cheers!

  8. #8

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    No pin holes noted...it is a new bellows, on a new camera, and it appears to be well glued. Placed a holder in the camera and put a flashlight in the lens hole, no issues noted. When I look into the front of the camera (with no lens) and shine a light onto the holder, I do see about 1/2 inch of the actual cherry part of the holder....by the flap. In other words, could I be getting reflections from the wood? But then again, why only 'flare' the corners (top and bottom)?

    Yes Bill the flap does 'hang out' a little from the gg back. Could be the flare is coming from the side not currently being exposed...

    The flare is darker near the corner, both top and bottom, on the flap end and becomes less dark as it 'flares' into the negative. A small fan shape about 1 1/2 inch from the corner to the furthest edge of the fan...It is surprising that it is both the top and bottom corners of the flap end where I load the film.

  9. #9
    David A. Goldfarb's Avatar
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    I also suspect an issue with the way the holder seats in the back. It's a modern camera, so there shouldn't be the kinds of problems I've had with my 1890's 11x14" camera, but since there isn't a single standard for 7x17", one never knows.

    Are the holders a tight fit? If they are very tight, this can be an issue with big filmholders. The lock rib should fit easily in the groove on the back, and there should be a little play between the edge of the holder and the frame of the back. If your Phillips has a removable back (which I suspect it might not), one thing you can do is insert the holder and remove the back (with the darkslide in place, obviously) to check carefully that the holder is seated flat in the back.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
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  10. #10

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    Thanks David, the holders appear to be seated fine. I ran a flashlight around the holder while I had someone else look into the lens hole in the dark...no apparent leaks.

    The more I think about it the more I think it may be the holders. I think they may be the older style S & S. The reason that it has been so hard for me to 'detect' is that if I photograph in shade, or cloudy conditions, or I remember basically shielding the holder from any sunlight...no problems. But, if the holder has any prolonged time in the sun, I get corner problems. And to make matters worse, I painted the flaps black, which appeared to help, and maybe did to some degree, with limited exposure in the sun? But yesterday I was out in the bright sun, and ruined 6 images with flare in corners, but did not ruin images taken in the shade. I thought perhaps I was getting bellows flare, but I'm not shooting into the sun and am using 'mostly' coated glass.

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