Film-Tech Forum ARCHIVE: Positive dirt that changes each scene?

This is topic Positive dirt that changes each scene? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by John Hawkinson (Member # 1135) on 04-21-2007, 10:41 PM:

So, over in my FITA post about Passenger (1975), I noted:

"There's a huge amount aperture dirt and hair just outside the 1.85:1 area that I do not understand; occasionally it makes it into the 1.85:1 frame. It is positive (black) that varies from camera cut to camera cut, so I don't understand (originated on reversal stock? That seems unlikely!). Workprints used for the IP??"

Anyone have any clue about this? I'm still kind of puzzled about it after mulling over it for a while.

--jhawk

Posted by Scott Norwood (Member # 30) on 04-21-2007, 11:14 PM:

Is it consistent from _every_ _other_ scene to every other scene? If so, then the negative was probably cut into A&B rolls, rather than as a single strand. All 16mm prints are printed from A&B rolls, but this seems to be less common for 35mm. Also, fades and dissolves look slightly different when made from A&B rolls vs. single-strand.

Posted by John Hawkinson (Member # 1135) on 04-22-2007, 07:10 AM:

Hmm. I no longer have the print, so I'm not in a position to tell.
Though I don't really see how A/B printing is more likely to yield positive dirt.

Actually, maybe my thinking was backwards. Dirt in the camera aperture -> white dirt on the negative -> black positive dirt on the release prints.

So maybe it's just a really dirty camera.

--jhawk