[APML] Film Color Response

["William R. Mattil" <wrmattil@ix.netcom.com>]

Hello,

I just recieved back some pictures that I took from my last dark-sky
trip and ran into something that makes me a bit curious. On two
consecutive nights I shot some piggyback pictures of up to 1 hour
duration. First night I used Kodak Royal Gold 100 ASA and the second
night I used some Fuji Superia REALA 100 ASA with the same exposures.
The differences between these two films are startling. The Kodak shows
good red response (M42 appe ars red as does the flame and horsehead. The
Fuji shows no red nebulosity at all. M42 is green, Flame and Horsehead
are not visible at all. But Betelgeuse is red.... curious. Is this
normal for this film ? (the fuji). The archives seemed to indicate that
it wasn't a bad film. I also have a few dozen rolls of Fuji Superia 800
ASA that I am afraid to use now because of this. I seem to recall that
Fuji may have changed their emulsions (4th layer technology ?) and this
wasn't good for Astro work. Can anyone fill in blanks here ?

Thanks !

Bill
-- 
William R. Mattil	| Fred Astaire wasn't so great.
wrmattil@ix.netcom.com	| Ginger had to do it all backwards
(972) 399-4106		| and... in high heels.

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