Re: About filter reflection factors....

[tom@xxxxxxxxxxxxxxxxxxxxxx (Tom Benedict)]

Toughie.  Here's a question:  Any idea how different that would be for:

        Unexposed HIE

        Unexposed, but developed HIE (black)

        Exposed and developed HIE (clear)

        Exposed, but not developed HIE

At a guess I'd say the first and last would be very close to each
other (identical?), and the middle two would bear very little
resemblance to anything else.

Here's why I'm asking: I habitually save chunks of film at various
states and stick them in 35mm slide mounts in case I need them later.
This has been useful on a number of occasions, especially when
spectral transmission is in question (never done reflectivity).  I've
got the two developed states of HIE, but not the undeveloped (I chuck
my film leaders).

The bottom line is that I'm probably not going to be shooting any IR
for a while, but I've got the right test setup to tell you the
spectral reflectivity of the film if I had it to test.

Tom

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