Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,219   Posts: 1,532,224   Online: 822
      
Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 27
  1. #11
    lxdude's Avatar
    Join Date
    Apr 2009
    Location
    Redlands, So. Calif.
    Shooter
    Multi Format
    Posts
    6,622
    Quote Originally Posted by Usagi View Post

    There's was one good tutorial in the net, but I can't find it any more.
    Maybe the one at Kyphoto. They have Jon Goodman's instructions there. Google kyphoto and you will see the link for Jon Goodman's seal info.
    I do use a digital device in my photographic pursuits when necessary.
    When someone rags on me for using film, I use a middle digit, upraised.

  2. #12
    DWThomas's Avatar
    Join Date
    Jun 2006
    Location
    SE Pennsylvania
    Shooter
    Multi Format
    Posts
    2,221
    Images
    64
    Yes, that horizontal line is likely the seal where the back opens, up toward the ISO dial/latch.

    See my PBase SQ-A page, toward the bottom. The shot labeled "Oh my Back!" is from a back with practically no seal left. It's the film coming off the supply spool that gets hit, not the film in place at the frame mask, so it's appearance can be variable depending on ambient light and how fast you wind through frames.

    The good news is it fixable!

    (Late catching up with this, having no power at home since Monday night.)

  3. #13
    ParkerSmithPhoto's Avatar
    Join Date
    Jan 2010
    Location
    Atlanta, GA
    Shooter
    Medium Format
    Posts
    797
    Images
    6
    Quote Originally Posted by Pandysloo View Post
    So I opened it up and gave it an inspection. The black splotches were caused by the deteriorating seal at the top of the film back next to the ISO dial on top
    Indeed. I had the same problem and got through many years by making a band out of black elastic and placing it over the back like a cuff! It was pretty low tech but it worked.

    I finally sent it off to Koh's Camera and he fixed it perfect for a crummy $20. Wish I hadn't waited so long. He's the Bronica guy.
    Parker Smith Photography, Inc.
    Atlanta, GA

    Commercial & Fine Art Photography
    Portrait Photography

  4. #14
    Pandysloo's Avatar
    Join Date
    Sep 2012
    Shooter
    Medium Format
    Posts
    30
    Quote Originally Posted by DWThomas View Post
    Yes, that horizontal line is likely the seal where the back opens, up toward the ISO dial/latch.

    See my PBase SQ-A page, toward the bottom.

    Just repaired my back using your page as a guide. Super helpful stuff! I will report back once I run a roll through it...

  5. #15
    Pandysloo's Avatar
    Join Date
    Sep 2012
    Shooter
    Medium Format
    Posts
    30
    Update: I fixed the light leaks for the most part, but since 95% of my shooting is done in cloudy/rainy weather, I figure it wasn't much of a test.

    I recently did a lot of shooting in intense sunlight and found a good portion of my negs ruined by light leaks. This is just one of many photos afflicted, all of them with a leak of the same intensity and location.

    Click image for larger version. 

Name:	602437_10151609372307808_2041266596_n.jpg 
Views:	23 
Size:	80.1 KB 
ID:	70853

    I'm trying to figure out where to locate this particular leak so I can go in and add some more foam. The image is flipped upside-down, correct? So based on this the leak is coming from the center, spanning downwards on the left side of the back?

  6. #16
    DWThomas's Avatar
    Join Date
    Jun 2006
    Location
    SE Pennsylvania
    Shooter
    Multi Format
    Posts
    2,221
    Images
    64
    Hmm. I wonder if the seal across the hinge part of the back is gone/deteriorated? (#3 in this shot)

    I think the leak is stronger toward the right side, viewing the camera from the back when the film is upside down -- but it could just mean the sun was on that side!

    These things can be weird, the actual leak may be near the supply or take-up spool and not striking the actual mask frame area. In such a case, it's either the frame before, or the frame after the shot that gets light struck. My hands-on personal experience with these problems is still fairly limited (thank the Flying Spaghetti Monster!) so it's difficult to speculate on the full range of possibilities.

    Another dubious thought is that possibly the light baffle behind the mirror in the body isn't closing all the way, and light comes in through the lens and around the sides of the mirror. As I type that it sounds far fetched, but obviously something is not in factory spec.

    An additional vague possibility (based on analysis, not experience! ) is that the back isn't seating tightly due to the little retaining hooks being worn or loose or something.

    I suppose black (gaffers') tape could be carefully applied to help in isolating the light path. If all the back attachment and closure stuff is taped and it still happens, that might suggest the light baffle. If the joint between the back and the body is taped and you still get it, it pretty much has to be one of the long seals at the top or bottom.

    You could also plan some real test cases -- put the camera in the sun with a lens cap on and pretend to do some exposures, change the angle of the light hitting it, etc.

    That's what passes for my thinking -- no charge!
    Last edited by DWThomas; 06-28-2013 at 04:56 PM. Click to view previous post history.

  7. #17
    DWThomas's Avatar
    Join Date
    Jun 2006
    Location
    SE Pennsylvania
    Shooter
    Multi Format
    Posts
    2,221
    Images
    64
    And the next day ...

    I've been thinking (smell the smoke!) the fact that there appears to be light struck area on the film rebate pretty much means it's a seal problem. The frame mask is between the film and the body shutter, and even the dark slide and the back to body joint. The rebate is more open to exposure between the spools and the insert rollers.

    There -- how's that for profound pronouncement!

    They are really neat and capable cameras, but the back light seals appear to be a weak spot. And of course virtually any backs around are at least a dozen years old -- and maybe thirty!

  8. #18
    Pandysloo's Avatar
    Join Date
    Sep 2012
    Shooter
    Medium Format
    Posts
    30
    What exactly do you mean by "rebate?"

  9. #19
    DWThomas's Avatar
    Join Date
    Jun 2006
    Location
    SE Pennsylvania
    Shooter
    Multi Format
    Posts
    2,221
    Images
    64
    Quote Originally Posted by Pandysloo View Post
    What exactly do you mean by "rebate?"
    The edges of the film with the manufacturer's markings on them; that is, outside the picture frame area. That portion is normally protected by the mask when the actual frame is exposed, so if it is light struck, the light must be catching it when another frame is lined up for exposure.

  10. #20
    Pandysloo's Avatar
    Join Date
    Sep 2012
    Shooter
    Medium Format
    Posts
    30
    So you think the leak can be located somewhere around the spool of the back, and not the darkslide slot? That certainly helps!

    What type of cheap film should I run some tests with? If this was 35mm I could just run to the drug store and grab something cheap...

Page 2 of 3 FirstFirst 123 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin