I've read a draft of the SCS report authored by Kristin Thompson that Henry
Jenkins mentioned.  He's got it right: the report cautiously advises that
the use of frame enlargements would be protected by the fair use provision
of the copyright act.  However, this does not hold for production stills,
since they are actually independent works, not "quotations" from another
larger work.  Some production stills, however, are in the public domain
because they were released for publication by the studios.  And once the
studio approves of the publication in magazines and newspapers without
copyright notice, the production still is in the public domain.
One's publisher may feel differently, however.  Not all publishers are
willing to accept the fair use argument (though many are).
I should make it clear, however, that this information is from a draft of
the report and not the final report itself.  This draft is essentially
complete, but needs a final check from the attorney that is working with the
SCS committee.
Regarding the equipment for making frame enlargements: there is a device
called a Duplikin that attaches to a 35mm camera that allows one to copy a
16mm frame.  It also comes in a version for copying 35mm frames.  The
problem with this device is that it crops the frame about 10% so that it
makes a nice looking slide, but one that is not exactly an accurate
reproduction of the original.  The alternative is to use a slide duplicating
attachment.  This is more accurate, but also more cumbersome to use.
As far as images from video: I don't do it that often, but I have good luck
just darkening the room and using a shutter speed of 1/25 second right off
the screen.
James Peterson
University of Notre Dame
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