M4-P is damaging film. Help!

[maggieo]

Hi y'all. The last few rolls of film that I've run through my M4-P have been coming back from the lab with little tears in the emulsion that look like this when printed or scanned:

Any ideas of what might be causing these scratches/gouges? I've looked in the camera and run my fingers over things, but there's nothing that's immediately obvious. Any ideas as to what's causing it and what can be done to fix it?

 

[Vickko]

Is it on every frame? The only thing that would "touch" every frame is the shaft with the sprocket. I'd examine something that would correspond to the "height" of the damage, from the bottom of the camera (reversed image). Maybe there is a chunk of debris that is literally stamping a dimple in the film.

Debris on the camera body would cause a long continuous scratch, not regular dimples.

Good luck

 

[maggieo]

It runs the entire length of the film.

I haven't found any debris. I swept out the inside of the camera and I'll know if it helped after I develop the roll I shot after cleaning it.

 

[newsgrunt]

I'd go with lab issues

 

[Haigh]

Maybe you could obtain a cheap roll of film and expose it then get it processed at another lab if possible.

 

[maggieo]

I'd go with lab issues

Then why is the M4-P the only camera that does this? The M2, the F3 and the XA all came back fine. It's gotta be the camera.

 

[maggieo]

Maybe you could obtain a cheap roll of film and expose it then get it processed at another lab if possible.

Same result, no matter what the lab.

 

[newsgrunt]

take some cotton balls and see if it catches anywhere. a long scratch I can understand but small tears baffles me as I can't really think of any place where the emulsion has deep enough contact to leave these marks. is there any noticeable direction to the marks ?

 

[maggieo]

take some cotton balls and see if it catches anywhere. a long scratch I can understand but small tears baffles me as I can't really think of any place where the emulsion has deep enough contact to leave these marks. is there any noticeable direction to the marks ?

The seem to be discreet tears or little pits in the emulsion. Maybe I got a bad batch of Portra? I guess I'll know when I process the XP2 I just shot.

 

[Vincent.G]

Your takeup spool blades?

 

[Richard G]

Not evenly spaced, and at a rate of more than 8 per frame, potentially. Likely something on the pressure plate intermittently catching the emulsion. Is the pattern slightly different each frame, or is the sequence you've marked alway repeated exactly? Polishing the pressure plate might do the trick.

 

[Leigh Youdale]

What about something in the felt seal where the film exits the cartridge?
But as you say it could be a manufacturing fault, although those are pretty rare.

 

[johannielscom]

When checking, remember to look at the bottom half of the film trail, since the lens projects the image onto the film upside down!

Did you have any film torn in your camera recently? A piece of film caught in the shutter curtain guide rails might make an irregular pattern, or maybe soemthing caught the edge of the curtain?

Good luck finding it!

 

[maggieo]

Interestingly that pattern of damage only appeared on the five rolls of Portra 400NC that came bundled together. I'm blaming the film at this point. The XP2 came back fine.

 

[newsgrunt]

if it does turn out to be the film, wonder if might be worth seeing if you can get replacement rolls...

 

[coelacanth]

Can't believe it's the camera. They look like very fine pin-hole shape. If it's on pressure plate (or anywhere in camera), it should be more of dragging marks, don't you think?

I think it's either the film or the lab...

 

[Chris101]

What about something in the felt seal where the film exits the cartridge?
But as you say it could be a manufacturing fault, although those are pretty rare.

Rare? I don't think so - I have had 3 rolls of Kodak b&w film being 24 exposures even though the cassette was marked 36 (2 rolls) and previously exposed (all the way to the edges for 1/2 the roll - the shadow line was diagonal. I could not have been responsible for that!)

Over the last 35 years I don't think I have found 3 bad rolls. QC is becoming very spotty in Kodak factories of late.

 

[maggieo]

Can't believe it's the camera. They look like very fine pin-hole shape. If it's on pressure plate (or anywhere in camera), it should be more of dragging marks, don't you think?

I think it's either the film or the lab...

I think it's the film. I know the scratches from my lab (sadly) and those odd marks are ONLY on those five rolls of Portra 400NC that came in a 5-pack.