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Re: [APML] Supra 800 film



Hi Chris:
Looks like another nail in Supra800's coffin. Not a good film for anything with both OIII and H-alpha. I did find some reds (no cyan) in a very underexposed Supra800  image of the Rosette but the image was no denser than with E200 for the same exposure, so reciprocity failure is quite significant.
Thanks....
Bert
 
Bert Katzung
katzung1@attbi.com
www.astronomy-images.com
 
 
----- Original Message -----
Sent: Thursday, April 11, 2002 6:25 AM
Subject: RE: [APML] Supra 800 film

Bert, I did quite a few tests of Supra 800 and no reds either.  They use is quite a lot in the northern parts of the world for Auorora photography.
 
Chris Schur
 
-----Original Message-----
From: owner-astro-photo@seds.org [mailto:owner-astro-photo@seds.org]On Behalf Of Bert Katzung
Sent: Wednesday, April 10, 2002 3:22 PM
To: astro-photo@seds.org
Subject: Re: [APML] Supra 800 film

Hi Craig and Pat and other film people:
Well, here's some more data on the Supra800 question---I took some quick and dirty shots last weekend with Supra800 and EliteChrome200 (aka Ektachrome200) and got the results this morning. I don't see much in the way of reds! In fact, I found the cyan shift of the Supra rather startling. Furthermore, the supposed greater dynamic range of negative vs slide film was cancelled out by what I believe is pretty severe reciprocity failure. These were all UNhypered film shots and only 20-25 minute exposures. Scanned from the film with the default settings on my Polaroid SprintScan 35 Plus, so there should be no scanner-induced shifts.
 
 
I can't rule out that the processor did something strange with this one roll of Supra, but I had some Fuji NPG800 processed at the same time that turned out normally. Anybody else have some Supra 800 results posted that we can compare?
 
Bert