View previous topic :: View next topic |
Author |
Message |
iml
Joined: 02 Nov 2009 Posts: 6 Location: UK
|
Posted: Fri Nov 06, 2009 11:06 am Post subject: Newbie with light leak |
|
|
Just acquired a Speed Graphic with spring back and 135/4.7 Optar. The bellows look clean and in good condition, although I haven't yet had the camera apart to have a good look at it. I took a few test shots with it, using 2 different dark slides, and all of them have what looks like a light leak. Here's 2 examples:
Anybody have any suggestions as to the most likely culprit? I'd like to try to fix this myself, although I'm no great expert at camera servicing, so suggestions as to what to look for would be very helpful.
Thanks.
Ian |
|
Back to top |
|
 |
Les
Joined: 09 May 2001 Posts: 2682 Location: Detroit, MI
|
Posted: Fri Nov 06, 2009 2:23 pm Post subject: |
|
|
Find a mini-maglight.
Find a dark or at least semi- dark room.
Remove the back: two screws on the springs if it's a Graphic back, push and slide the chrome arms if its a Graflok back.
extend the bellows as far as possible. remove the front lens board.
take the head off the mini-mag light and stick the light bulb inside the bellows.
Look at the outside for pin holes.
Note: Pinholes find the tiniest cracks and corners to propagate. Move the light around and into the corners (the small bulb doesn't get hot enough to hurt anything.
Another option is to use a compact fluroescent bulb on an extension cord.
I suspect it's a pinhole because the fog in the second image is an image, and I suspect the first neg's fog is a partial image too.
Either that or this building was built on an ancient cemetery and this is just the beginning of what will be a great movie.  _________________ "In order to invent, you need a good imagination and a lot of junk" Thomas Edison |
|
Back to top |
|
 |
iml
Joined: 02 Nov 2009 Posts: 6 Location: UK
|
Posted: Fri Nov 06, 2009 4:06 pm Post subject: |
|
|
Thanks Les, that's very helpful. Will give it a try over the weekend. |
|
Back to top |
|
 |
troublemaker
Joined: 24 Nov 2003 Posts: 715 Location: So Cal
|
Posted: Sun Nov 08, 2009 6:29 pm Post subject: |
|
|
I haven't tried Les's method, but sounds like a good one. I use one of those old elongated fishtank bulbs in the dark room. Same drill. That's inside out. For outside in I use bright light like a Mag or the spot on my headlamp. You'll want to light test with the film holder you used in place, and look towards the back with the lens board removed.
Check everything out by process of elimination. You can put film or paper in holders and put out in light to check for leaks on the film holders also. There 's info here and elsewhere on a good method for that test.
Another culprit I found once that looked something like film holder light streaks turned out to be very small cracks in the lid of my daylight developing tank. The reason I mention this and to check other issues is that small pin holes in the bellows aren't that big a deal. Just keep dark slides in until ready to expose and replace right away. Your images have a look as if maybe the film holder is either not seated flatly in the camera back, or lifted when pulling the darkslide etc... Hold the viewing screen firmly against the camera back and holder when pulling dark slides.
Just some added thoughts for you to check...
Have fun. |
|
Back to top |
|
 |
iml
Joined: 02 Nov 2009 Posts: 6 Location: UK
|
Posted: Sun Nov 08, 2009 8:14 pm Post subject: |
|
|
Thanks again.
I've done the light test and found a couple of pinholes, so tomorrow I'll find some suitable vinyl repair gloop to fill them.
Many thanks for the help, really appreciated. |
|
Back to top |
|
 |
iml
Joined: 02 Nov 2009 Posts: 6 Location: UK
|
Posted: Fri Nov 13, 2009 4:37 pm Post subject: |
|
|
Great, a couple more test shots are hanging up to dry and it looks like the leak is fixed  |
|
Back to top |
|
 |
Henry
Joined: 09 May 2001 Posts: 1648 Location: Allentown, Pennsylvania
|
Posted: Fri Nov 13, 2009 9:50 pm Post subject: |
|
|
So what did you use for the "gloop"? (not that it wold be available over here...) |
|
Back to top |
|
 |
iml
Joined: 02 Nov 2009 Posts: 6 Location: UK
|
|
Back to top |
|
 |
Henry
Joined: 09 May 2001 Posts: 1648 Location: Allentown, Pennsylvania
|
Posted: Mon Nov 16, 2009 6:00 pm Post subject: |
|
|
Thanks. That link is so long that it ate my computer---twice! Even converting it to TinyURL was no help. I'll google up "halfords" and take it from there. Glad your repair was effective! |
|
Back to top |
|
 |
45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
|
Posted: Mon Nov 16, 2009 9:36 pm Post subject: |
|
|
The Loctite 5940 Black Silicone sealant is an excellent choice for patching small holes in the vinyl bellows, however the tape will come off in a relatively short time and leave a very sticky, hard to remove residue that will migrate onto adjoining areas and your fingers. I strongly recommend you remove the tape now and clean any residue off. Window cleaner such as Windex or Isopropyl Alcohol will work well now. Black fabric paint applied to the inside of the bellows works well also. Use the washable kind if available.
Plasti Dip is another product that works very good for vinyl bellows repair. _________________ The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU. |
|
Back to top |
|
 |
bertsaunders
Joined: 20 May 2001 Posts: 577 Location: Bakersfield California
|
Posted: Mon Nov 16, 2009 11:12 pm Post subject: patching bellows |
|
|
Caution: Plasti-Dip unless dried thourly will glue (adhear to itself) and it is very tough to seperate without damaging original material!
Have a nice day......Bert |
|
Back to top |
|
 |
iml
Joined: 02 Nov 2009 Posts: 6 Location: UK
|
Posted: Tue Nov 17, 2009 8:55 am Post subject: |
|
|
Thanks for the warning about the tape. |
|
Back to top |
|
 |
bruiser
Joined: 15 Oct 2006 Posts: 260 Location: Northern NSW Australia
|
Posted: Tue Nov 17, 2009 11:36 am Post subject: |
|
|
Equinox Photographics have bellows repair stuff too. Go to http://www.equinoxphotographic.com/large.htm and scroll down to the pink/purple text, about 2/3 down the page. $6.50 + $3 postage in the US, obviously more to the UK.
Cheers,
Bruce |
|
Back to top |
|
 |
|