Canon P scratching my film?

[thereabouts]

Hi

I'm getting this issue from different labs (and scanners) so I think this must be the camera.

I am getting horizontal scratches on my films. I've attached a bit of scrap film as an example, as it's easier to see than on my actual images.

I *think* it may be happening when I rewind the film at the end of a roll, as it doesn't seem to go as smoothly as I would have thought.

That said, I'm only recently coming back to film since 20 years ago, so I can't really remember. But this particular roll was the worst and it also seemed to be the hardest to rewind at the end.

I'm making sure that I turn the dial away from the 'A', before rewinding.

Anyone got any ideas?

 

[Sid836]

An easy way to spot it is taking some sort of plastic sheet, cutting a stripe at film width, open the camera's back and run it by gently pressing in against the back of the curtains in the film chamber, observe for hair lines on it and then try it on the film pressure plate.
Locate the point that generate the scratch and rub it flat.

 

[oftheherd]

An easy way to spot it is taking some sort of plastic sheet, cutting a stripe at film width, open the camera's back and run it by gently pressing in against the back of the curtains in the film chamber, observe for hair lines on it and then try it on the film pressure plate.
Locate the point that generate the scratch and rub it flat.

If you have done this, what did you use to rub out scratch generating areas? The best I personally know of is Croakus cloth, which is a very fine sandpaper. When I was a young'un the military used it to remove small rust areas without removing the blueing.

 

[Mackinaw]

Any chance there's a piece of grit caught in the film cartridge felt? That can cause scratches shown in your pic too.

Jim B.

 

[thereabouts]

Thanks for the tips. The plastic film technique sounds a bit tricky for me, but I'll have a try.

Any chance there's a piece of grit caught in the film cartridge felt? That can cause scratches shown in your pic too.

Jim B.

Possible, but it's happened with several films. I blew out the inside of the camera with some air last time, but it hasn't done any good.

 

[thereabouts]

Actually, upon inspection, the film sprocket appears to not turn completely smoothly on rewind. It's as if it is slightly bent/warped maybe? It turns smoothly, and then needs a slight bit of extra force to get it over a 'hump', before it turns smoothly again.

Could that be the reason?

 

[Steve Bellayr]

I had something like that years ago on a Nikkormat. Check to see which side of the film the scratch is on. From the photograph I assuming that it is a horizontal scratch. If it is the side that comes in contact with the pressure plate then there is some dirt on the pressure plate. If, so then clean the plate with a gentle solvent. I used Toluene but any gentle solvent lightly used should clean the plate.

 

[thereabouts]

Thanks to everyone for the comments so far. Unfortunately, I am still not much further in resolving this problem.

I cleaned everything I could find to clean, but to no avail. I am 95% certain that the scratches are on the dull side (emulsion) of the film. Which means that one of my initial suspicions of where the paint is worn away, (see circle on attachment 1) is probably not the issue. This also probably means that the issue is not the pressure plate?

I've attached some shots of the inside of the camera. Can anyone see anything that I might have overlooked?

Thanks for any suggestions.

 

[thereabouts]

A couple more pics.

 

[rodt16s]

Put a section the scratched film back into the camera and check if you can detect anything likely to contact the film where the scratches are.
Also sacrifice a partial roll by winding on a few frames, but only rewind a section back into the canister to check whether it is being caused on the rewind

 

[thereabouts]

Thanks.

Yep, I've done the first part and can't see anything. I will have to sacrifice some film I suppose.

I suspect that it is indeed the rewind that is causing the issue. Which is a pain. I probably should just give it to a professional to try and fix.

 

[Mackinaw]

If the scratches are on the emulsion side, try to see where in the camera contact with the film could happen. If you think the scratches are happening during rewind, maybe the film cartridge is shifting slightly in it's chamber causing the film to hit the body.

Jim B.