Dan Daniel
Well-known
A while ago I posted asking about a sporadic light leak I was having on a Rolleiflex 2.8C Xenotar. There were various suggestions made, and I spent a couple of months trying various solutions. I think I may have found it.
First, a sample of the leak:
The leak was always in this position, almost always this shape, with the density varying. This spot is a pretty precise match for the place where film would be coming off of the spool in the lower/source film chamber. The leak varied in occurrance. Some rolls would have one small leak, another roll three huge ones. I tried to find a pattern but I couldn't.
I dreamed of working at a photo lab where I could just run roll after roll of tests through a machine instead of needing to hand develop each roll, wondering if things would be ok.
I tried adding foam around the door, with special emphasis on the lower section. I tried adding telescope light-killing flocking to the lower and upper film chamber, with special attention to the silver spring tab in the lower center area. I added thin gaskets to both spool knobs.
I thought I had the answer by applying black vinyl tape to the whole lower front and sides of the back to close off any leaks here. But after a few rolls- it happened again. And again.
One area that always made me wonder is the slot on the wind side of the lower/source chamber where the automatic film/counter lever is located. I knew that there was a very thin brass shim as a cover over this area right underneath the side panel on another Rolleiflex I had opened. Maybe someone has forgotten to replace this?
I opened up the side. Brass shim was there. Playing with a lamp and shade, I could see light coming through the slot in the film chamber, the one that worried me. I decided to add an extension to the brass shim, and made one from thin black vinyl that went from one side to the other and cut below the wind mechanism central gear. With this tacked in place with white glue, no light appeared to come through the slot.
A couple of rolls were perfect, and I relaxed into thinking that the problem was solved. But alas, it returned.
So how in the world was light able to even get near this area? I tired using black paint to seal the edges of the side panel, but the leak was still there.
I remembered someone, maybe here or maybe on photo.net, mentioning a bellows leak. He said that a collar around the viewing lens had stopped light from streaming behind the lens board, making the small leak in his lens bellows meaningless.
Looking at the wind side with the side panel removed, light can come from behind the lens board into the lower side through openings for the shutter cocking mechanism. So what the heck....
All I had was an ADOX 120 film cannister. I cut the top off, trimmed it to fit, and installed it around the viewing lens (after removing the focusing hood, obviously). It is cut to not bump the mirror on infinity focus, and to still cover (most of) the opening when the lens is at closest focus.
So far, after more than a week and 8 rolls, not one glimmer of a leak. I've racked the focus back and forth, left it at different positions, pointed all parts of the camera towards the sun for extended periods. No sign of a leak.
I don't work on cameras all the time. Maybe I am blowing smoke. Maybe the real solution happened in a completely different manner. But however it happened, the leak appears to be gone.
I thought I would put this in the record in case it drives someone else nuts. If it turns out that what I am reporting as the solution ends up not working, I will come back and report it.
A few photos of the mask. The tension of the material holds it on the small lip at the back of the viewing lens. Installation is tricky as you are floating between the back element of the lens and a front surface mirror- be very careful!!
Sorry for the length.
First, a sample of the leak:
The leak was always in this position, almost always this shape, with the density varying. This spot is a pretty precise match for the place where film would be coming off of the spool in the lower/source film chamber. The leak varied in occurrance. Some rolls would have one small leak, another roll three huge ones. I tried to find a pattern but I couldn't.
I dreamed of working at a photo lab where I could just run roll after roll of tests through a machine instead of needing to hand develop each roll, wondering if things would be ok.
I tried adding foam around the door, with special emphasis on the lower section. I tried adding telescope light-killing flocking to the lower and upper film chamber, with special attention to the silver spring tab in the lower center area. I added thin gaskets to both spool knobs.
I thought I had the answer by applying black vinyl tape to the whole lower front and sides of the back to close off any leaks here. But after a few rolls- it happened again. And again.
One area that always made me wonder is the slot on the wind side of the lower/source chamber where the automatic film/counter lever is located. I knew that there was a very thin brass shim as a cover over this area right underneath the side panel on another Rolleiflex I had opened. Maybe someone has forgotten to replace this?
I opened up the side. Brass shim was there. Playing with a lamp and shade, I could see light coming through the slot in the film chamber, the one that worried me. I decided to add an extension to the brass shim, and made one from thin black vinyl that went from one side to the other and cut below the wind mechanism central gear. With this tacked in place with white glue, no light appeared to come through the slot.
A couple of rolls were perfect, and I relaxed into thinking that the problem was solved. But alas, it returned.
So how in the world was light able to even get near this area? I tired using black paint to seal the edges of the side panel, but the leak was still there.
I remembered someone, maybe here or maybe on photo.net, mentioning a bellows leak. He said that a collar around the viewing lens had stopped light from streaming behind the lens board, making the small leak in his lens bellows meaningless.
Looking at the wind side with the side panel removed, light can come from behind the lens board into the lower side through openings for the shutter cocking mechanism. So what the heck....
All I had was an ADOX 120 film cannister. I cut the top off, trimmed it to fit, and installed it around the viewing lens (after removing the focusing hood, obviously). It is cut to not bump the mirror on infinity focus, and to still cover (most of) the opening when the lens is at closest focus.
So far, after more than a week and 8 rolls, not one glimmer of a leak. I've racked the focus back and forth, left it at different positions, pointed all parts of the camera towards the sun for extended periods. No sign of a leak.
I don't work on cameras all the time. Maybe I am blowing smoke. Maybe the real solution happened in a completely different manner. But however it happened, the leak appears to be gone.
I thought I would put this in the record in case it drives someone else nuts. If it turns out that what I am reporting as the solution ends up not working, I will come back and report it.
A few photos of the mask. The tension of the material holds it on the small lip at the back of the viewing lens. Installation is tricky as you are floating between the back element of the lens and a front surface mirror- be very careful!!
Sorry for the length.
Last edited:
sreed2006
Well-known
That's persistence.
I cannot envision the path the light would have to take to make that spot on the negative if it came from the viewing lens. How does the light get from the upper chamber to the film?
I cannot envision the path the light would have to take to make that spot on the negative if it came from the viewing lens. How does the light get from the upper chamber to the film?
Dan Daniel
Well-known
If the black shield I installed was removed, you would see that there is an opening at the back of the viewing lens that will allow light to flood behind the lens board. Best as I can figure, the light itself comes from the focusing hood and mirror.
Going down the right/shutter release side of the lens board, there is an open area feeding into the right side of the camera. This opening is where the shutter cocking mechanism connects the wind lever to the actual shutter unit.
Bounce along to the lower back corner of the right side, and the film sensor mechanism is located. If you look inside the back of the camera, where the film feeds from, on the right side is a small lever/plate. This lever travels into the camera's right side. I don't see light seals at this joint.
As to how light actually makes this strange trip, I do ont know. I haven't been behind thel ens board to see what kind of obstructions exist. The film sensor mechanism looks just like the one on a 2.8A Rolleiflex I have. I would imagine that it is a pretty standard unit? If so, why I have this problem and yet it isn't seen by others, mentioned by others, etc., confuses me to no end.
There is one person known for doing excellent work on Rolleiflexes who told me that he had seen a similar leak on the same model, once.
My interest is not having light streaks across my negatives at random shots. So far, so good!
Going down the right/shutter release side of the lens board, there is an open area feeding into the right side of the camera. This opening is where the shutter cocking mechanism connects the wind lever to the actual shutter unit.
Bounce along to the lower back corner of the right side, and the film sensor mechanism is located. If you look inside the back of the camera, where the film feeds from, on the right side is a small lever/plate. This lever travels into the camera's right side. I don't see light seals at this joint.
As to how light actually makes this strange trip, I do ont know. I haven't been behind thel ens board to see what kind of obstructions exist. The film sensor mechanism looks just like the one on a 2.8A Rolleiflex I have. I would imagine that it is a pretty standard unit? If so, why I have this problem and yet it isn't seen by others, mentioned by others, etc., confuses me to no end.
There is one person known for doing excellent work on Rolleiflexes who told me that he had seen a similar leak on the same model, once.
My interest is not having light streaks across my negatives at random shots. So far, so good!
sreed2006
Well-known
The small lever/plate on the right side that you mention, near the feed-spool, is the "back closed detector" as far as I can tell, and is called the "trip lever" in the parts manual. A plate attached to the camera back pushes that trip lever forward when the back closes.
Do you have the Service/Repair Manual for Rollei TLRs? You can download it from here:
http://www.kyphoto.com/classics/repairmanuals.html Scroll down the page till you find "Rolleiflex TLR". The manual does not specifically cover the 2.8C, but as you say that part of the camera should be fairly standard across models.
A drawing on page 231 of the PDF shows the trip lever and a shoulder screw that holds it in place (piece numbers 122 and 121). The quality of the PDF is not that great, but it might help you determine if there are missing parts on your camera.
Of course, if you have fixed it already, there's no point in tearing it apart again, is there?
Do you have the Service/Repair Manual for Rollei TLRs? You can download it from here:
http://www.kyphoto.com/classics/repairmanuals.html Scroll down the page till you find "Rolleiflex TLR". The manual does not specifically cover the 2.8C, but as you say that part of the camera should be fairly standard across models.
A drawing on page 231 of the PDF shows the trip lever and a shoulder screw that holds it in place (piece numbers 122 and 121). The quality of the PDF is not that great, but it might help you determine if there are missing parts on your camera.
Of course, if you have fixed it already, there's no point in tearing it apart again, is there?