Canon P light leak mystery: please help!

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I recently bought a black repaint Canon P from flyingpalm on eBay, and it has a light leak. This camera is in great condition otherwise. Here's what the first roll I put through it looked like:



OK, pretty bad. I went through a round of troubleshooting, firing a flashlight through every conceivable hole, including the rangefinder window, without finding anything. The lower baffle was a bit rattly, so I stuck it down fast with some adhesive felt. I replaced the hinge seals. I replaced the advance lever (for cosmetic reasons) and discovered the old one had been installed incorrectly, with the washers in the wrong order; thought that might have been the problem. I installed the new one right. I put another roll through, a different film this time, in case the film had been put in the cassette wrong, and I got this:



Definitely not as bad, but that could be because it was cloudy or that I waited less long between shots.

If I'm not mistaken, the light is hitting the film in two places, from the top of the camera. (Right? The image registers upside down and backwards, correct?) The leaks are consistent, in that they appear in the same place on every frame, and one side is always a little worse than the other. It seems to me, logically, that the leak is happening either while the frame is behind the shutter, OR, while it is wound around the takeup spool. The latter perhaps seems more plausible; it would explain why there are two leaks, one worse than the other: that is, the bad leak is where the light is shining directly on the film, and the less bad one is the layer beneath it.

I have another P and can't find any differences. The only thing is that there is some kind of little stop piece under the lever on the unrepainted P that is not on the repaint:



...but I can't see how that should make a difference.

I asked Youxin if I could sent it to him, but he declined; I assume he doesn't has time to troubleshoot this. He suggested putting some black tape over the hinge, and maybe I'll do that...but that's ugly.

Any ideas???
 
I had an essentially identical (although not quite as pronounced) looking light leak with my Canon 7. Replacing the hinge seal with a piece of fairly thick foam from one of Jon Goodman's kits seems to have sorted it out. (I tried shining a bright torch through every other part of the camera that seemed likely but couldn't see any other obvious leaks.)
 
I should have added that I initially tried a fairly thin piece of foam and the problem wasn't quite as bad but was still there.

Does anyone know whether there should be any foam in the channels for the backs on these Canon models?
 
Not sure about the precise fix, but the Canon Ps are known to have light leaks in the hinge area of the back & yes, were supposed to have foam for that area (deteriorates over time). I had 1 w/that leak & "solved" it (temporarily) by using 1/2 of the original neverready case.

I should have added that I initially tried a fairly thin piece of foam and the problem wasn't quite as bad but was still there.

Does anyone know whether there should be any foam in the channels for the backs on these Canon models?
 
OK, I found it! I ended up making a little flashlight out of a CR2032 and an LED:



I closed the camera and retreated into the closet. Turns out the leak is here:



I think that the repainting has rendered the precisely milled part surfaces kind of uneven. The screw above this area was not totally tight, so I did squeeze the top plate down and tighten it, and that lessened the amount of light getting through. But it doesn't solve the problem. Tape will, I guess? But I don't wanna put tape there. Perhaps I could put a little on the inside of the chamber...?
 
Not sure about the precise fix, but the Canon Ps are known to have light leaks in the hinge area of the back & yes, were supposed to have foam for that area (deteriorates over time). I had 1 w/that leak & "solved" it (temporarily) by using 1/2 of the original neverready case.

The only foam that is supposed to be in here is two little pieces at the top and bottom of the hinge. The channels are light-tight without seals. I did indeed replace those bits...
 
Just as I thought when I saw the negatives. It must be those two little seals at the top and bottom of the hinge. I once had a similar kind of problem when I had replaced all the seals but the material I used for the main light seal along the hinge was a bit too thick. I guess it pressed the top and bottom to open up just slightly and leak light.
 
OK, I found it! I ended up making a little flashlight out of a CR2032 and an LED:

Smart!!

The only foam that is supposed to be in here is two little pieces at the top and bottom of the hinge. The channels are light-tight without seals. I did indeed replace those bits...

Whatever it is gets very gooey.

Those seals must be very thin and must closed cell light proof foam. Tape is still easier. I have always thought those seals were just a bad design.
 
It wasn't the seals, though, it was the gap between the top plate and body. The adhesive felt I replaced the seals with seems to have worked fine. I clamped the two pieces together while tightening the screw and, yes, added a bit of gaffer tape to the outside, and the leak's gone. At least it seems to be! Next roll will be the tell, I guess...thanks all!
 
It wasn't the seals, though, it was the gap between the top plate and body. The adhesive felt I replaced the seals with seems to have worked fine. I clamped the two pieces together while tightening the screw and, yes, added a bit of gaffer tape to the outside, and the leak's gone. At least it seems to be! Next roll will be the tell, I guess...thanks all!

Bummer all the fuss, but it is a lovely camera to use. The only one I like better is the L1, which has a cloth shutter and a more a more interesting viewfinder.

But I always used external viewfinders with my P and L1. Both now in the hands of NHS and RFF members.
 
Hi, what a great camera is the P.

You should renew all light seals, they awll them on ebay you cut and paste.

Then make another test, i think it´s going to be just fine 😉
 
The main reason I sold my P years back was because of the viewfinder. Mine was flary, and annoying to use. I then picked up a Canon L1 with 50/1.2 which I still have and use. I agree with the praise of the viewfinder and the auto-correcting parallax pin located in the shoe. My L1, and the 25/3.5 lens and parallax-pin bright viewfinder, has been my main film camera this past month. A joy to use.

Jim B.
 
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