Purple dust in camera body (after shooting slide film)

punkzter

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I looked in the back of my Canon A1 yesterday after shooting a roll of kodak elite chrome (expired), and noticed quite a bit of purplish colored dust. I'm really curious where this could have come from. I'm not positive that it wasn't there before shooting the roll of kodak. It could have also been from a roll of fuji slide film. I looked at both of my recent rolls of film, and didn't notice any of the dust on the felt of the film canister.

In any case, has this happened to anyone before? I'm not super excited about it, and if it's a common occurrence with expired slide film, or other film, I may transition away from using it.

I was mostly able to clean it up, but it is in some hard to reach places and doesnt seem to just blow away. I'm mostly concerned about it getting into the shutter.

Thanks!
 

koraks

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Can you show a photo of the dust? And/or describe it in more detail? Have you looked at it with a loupe?
One thing that comes to mind is the flocking/felt material used on the light trap on 35mm cassettes. But some illustrations or further description would be useful to in/exclude options.
 

loccdor

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I've shot maybe 50 rolls of expired 35mm slide film in the last couple years, including a little Elite Chrome, and I haven't gotten dust from it.

Maybe one particular roll of film was stored in an odd way, like near makeup or painting supplies, I don't know. If it's from a light trap, those usually look like little threads. Do your slides retain an image of the dust blocking the exposure? Is it specks or threads/fibers?
 

Sirius Glass

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I suggest that the OP started with getting the dust vacuumed out. Using compressed air may drive the dust further inside the camera.
 
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punkzter

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I used a q tip to get most of the dust. It's a good point about compressed air. At this point, I'm pretty happy with how much I've gotten.

There is still some left that is harder to reach, so I have that to get.
 

koraks

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It's a little hard to tell from these photos. It doesn't look like the velvet flocking material from 35mm cassettes, that much is certain. Good to hear you were able to get it out.

The other day I was fixing a camera (actually AF mechanism of a lens) that my niece's toddler had dropped. The lens fixed up just fine, but there was really no cure for the amount of sand in that machine...she took the entire beach home inside it! Good thing it's a digital camera so the sand probably won't make it to where it can do a lot of damage.
 

loccdor

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Did the film develop ok? I wonder if something had caused it to partially disintegrate. If the film is leaving this much residue I'd be worried about the pictures.
 
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punkzter

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I haven't sent the film off for development. Yeah, I am a little concerned myself. I don't develop slide film myself, so I guess I'll just wait and see.
 
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punkzter

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The film leader wasn't concerning, but who knows. I also don't see any of the dust on the light trap, which I would have thought would capture some. Anyhow, I guess I'll send it off and wait to see.
 

koraks

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Well, see how the film turns out, but I struggle to think of a failure mode of the film itself that would leave this kind of residue. Well, one that doesn't involve dipping the camera in liquid nitrogen or something like that.
 
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punkzter

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well, just to clear things up, I didn't dip the camera, or the film in liquid nitrogen
 

Sirius Glass

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punkzter said:
I used a q tip to get most of the dust. It's a good point about compressed air. At this point, I'm pretty happy with how much I've gotten.

There is still some left that is harder to reach, so I have that to get.
Click to expand...

That should get most of the red dust out so that you could skip vacuuming it.
 

mshchem

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I've never seen anything like this. It's definitely purple! Crazy! I can't see how it is from the film. Was this a factory sealed carton? Is there a possibility that the film has been respooled? Almost looks biological, but never have I seen purple bugs???
 
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punkzter

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It was definitely purple(ish). Yes, the last few rolls of film that went through the camera came out of factor sealed boxes, so no possibility that the film was respooled. I can see why you say that it looks biological. I think that is just an issue with my ability to capture it in a photo.
 

Harry Callahan

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As it has collected most on the toothed wheel where the teeth enter the sprocket holes of the film, i`m wondering whether this purple dust is residue from the perforator. As a perforator does cut through the film, also through the emulsion - and as you say that the film was expired - it should be possible that the emulsion has oxidized "at the side".
Usually it`s only the surface (topcoat) of the emulsion having contact to oxygen, but with emulsion-dust from the perforating step oxygen could reach the emulsion from the side, not only on the surface.
I think i have a very old and undeveloped color film (40 years?), where the emulsion also looks purple... maybe some color films do turn purple if oxygen can make it through the topcoat.
With emulsion dust from perforating oxygen had it easier to make it to the actual emulsion.
Therefore i`m wondering whether this is dust from perforating the film.

On the other hand, if this was dust from perforating, it also should have collected on the light trap of the cartridge so... it`s probably not.
 
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punkzter

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The lack of the dust in the canister seal is a mystery to me. Unless this dust has been in the camera far some time. I have the past four rolls shot in my possession, and none have the dust on them. I really think that I would have noticed it.
 

mshchem

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Do you have more (a lot more)? May just be one of those mysteries. If it reoccurs with another film, well then you'll need to see a professional (about a nice digital SLR )
 
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punkzter

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Yes, I do have more. I have a large quantity of slide film in my freezer, which I intend to keep shooting. So yeah, I'm going to pay close attention to what happens in the future.
 

Harry Callahan

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punkzter said:
The lack of the dust in the canister seal is a mystery to me. Unless this dust has been in the camera far some time. I have the past four rolls shot in my possession, and none have the dust on them. I really think that I would have noticed it.
Click to expand...

...maybe the film sprockets did clean the seal when the film was spooled back into the cartridge... probably unlikely but not impossible...
 

MattKing

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Try as I might, I can't stop thinking of Jimi Hendrix every time I see the title to this thread.
And yes, I know, I need to Report myself.
 

RalphLambrecht

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Sirius Glass said:
I suggest that the OP start by vacuuming out the dust. Using compressed air may drive the dust further inside the camera.
Click to expand...

from experience, household vacuums are too strong and shutter blades may end up in the vacuum cleaner(don't ask how I know). careful blowing from a distance and from the side is safer.
 
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