Re: paper backing/halo (was: Out of date Konica 750 - 120 roll t

[tom@xxxxxxxxxxxxxxxxxxxxxx (Tom Benedict)]

I can see that a paper backing might leave fiber marks on the IR film,
but could something similar be done with some sort of plastic backing?
There are a number of plastics that are QUITE opaque to IR, many of
which could be extruded into a thin sheet for backing roll film.

I'd easily believe that different pressure plates reflect different
amounts of IR.  One of the tricky jobs with making an IR instrument
is the choice of paint and anodizing dyes used on the parts.  A number
of "black" paints are actually quite bright in the IR.  What's worse,
most paint manufacturers won't disclose what their pigment is because
it's proprietary.  Carbon-based paints are very black, even out to 10um
or so.  Finding one that will actually say, "carbon-based pigment" rather
than the usual "Ultra *NEW* and >IMPROVED< inCREDIble ->BLACK<- PAINT!"
is rare. ;)

Tom

------------------------------

Topic No. 15