allancobb Posted June 27, 2018 Share Posted June 27, 2018 Hello All, Some time ago, I acquired a nice and relatively rare Zeiss "Baby" Ikonta (520/18) with the Compur shutter and f/4.5 Tessar. Yes, I know the green covering probably isn't original. ;) The shutter seems to work nicely on all speeds and the lens has a few cleaning marks but that's about it from what I can tell. But on nearly every frame, I get this strange and inconsistent result: As can be seen, the bright spot is in the same general area in each frame, however, the intensity, size, shape and orientation is almost always different and somewhat random. This is with an assortment of shutter speeds and apertures. The film was expired Verichrome Pan on two different rolls, so I know it wasn't caused by the film. I've been using the same film-developing equipment for all my other processing, so I know it's not anything related to that. The different positioning leads me to believe it's not a camera light leak from either the back or the bellows (all seem light tight) or a lens flare. Could it be a mis-aligned shutter blade? Some odd form of lens flare? Opinions are welcome, thanks to all in advance! Cheers, Allan Link to comment Share on other sites More sharing options...
Dustin McAmera Posted June 27, 2018 Share Posted June 27, 2018 I would bet that is a bellows leak. Try this: cut a piece of card to make a flange round a flashlight, so you can light up the inside of the bellows from the back, without light spilling out. Then look closely at the corner folds, in a dim or dark room. 1 Link to comment Share on other sites More sharing options...
John Seaman Posted June 27, 2018 Share Posted June 27, 2018 Probably a pinhole in the bellows. The position, size & shape vary due to the direction and intensity of the incident light, and the length of time it is exposed, as the camera is handled between exposures. 1 Link to comment Share on other sites More sharing options...
allancobb Posted June 28, 2018 Author Share Posted June 28, 2018 Dustin, thanks; well, I made the flange you mentioned, and took it and the camera into my darkroom with a very bright flashlight and sure enough, there was a tiny pinhole in the lower corner of the bellows which otherwise escaped detection. John, what you say makes perfect sense now after seeing where the pinhole is then correlating the position and size of the light leaks in the images. The larger the “blobs,” the longer the camera sat between exposures. When they were very small or nonexistent, there was little time elapsing between the exposures. Now at least I know it’s a fairly straightforward solution to the problem, thanks to you both! Cheers, Allan Link to comment Share on other sites More sharing options...
kmac Posted June 28, 2018 Share Posted June 28, 2018 A good cure for bellows pinholes is a mixture of flexible fabric glue mixed with powdered pencil lead. I experimented with several different methods and this idea was the most successful: Using 400 grit wet&dry emery paper, rub it on black pencil lead (carbon) to make a powder, mix some in the glue to form a dark grey mix, place a small dob of the mix over the pinhole and allow to cure 1 Link to comment Share on other sites More sharing options...
rick_drawbridge Posted June 28, 2018 Share Posted June 28, 2018 Another good product is Liquid Electrical Tape, applied sparingly on a blunted toothpick. Leave for 24 hours before closing bellows; it dries flexible and permanent. 1 Link to comment Share on other sites More sharing options...
allancobb Posted June 28, 2018 Author Share Posted June 28, 2018 Thanks KMac and Rick, I was in the process of researching solutions; of course complete bellows replacement is the only true cure, but until then I can try these suggestions. I also heard something about Elmer's glue with pencil graphite mix, but I'm inclined to try these first. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now