RE: UV Box Heat Fogging?

From: Loris Medici ^lt;loris_medici@mynet.com>
Date: 11/22/05-11:46:49 AM Z
Message-id: <20051122174653.15C4A360C7C4@spamf3.usask.ca>

Well, if you can get maximum black with a specific exposure time and also
have a color that gives you paper white with that exposure time what's the
point in exposing for a longer time? I guess even a stouffer 31 step table
can show print density at step 31 (log 3.0) with enough exposure - it isn't
100% opaque to light.

-----Original Message-----
From: Michael Koch-Schulte [mailto:mkochsch@shaw.ca]
Sent: 22 Kasım 2005 Salı 19:05
To: alt-photo-process-l@sask.usask.ca
Subject: UV Box Heat Fogging?

Does anyone (else) experience what I think is heat fogging during UV
exposure. I'm using an eepjon like box with GE BL tubes 15/20s. I was doing
some max density tests on a new step wedge and started to double and triple
my exposure to see how effective my negative was at blocking UV when I
started to notice two things. The first was edge bleed on squares which
should have printed clean. The second was a general fogging toward my
densest squares, or so I think. It could also be the color ranges I've
selected are not providing enough contrast and therefore I'm just not able
to clearly define white. The thought occurred to me that once the emulsion
starts sitting in the oven for 24 minutes instead of say six perhaps heat
becomes an issue. Thx.

~m
Received on Tue Nov 22 11:47:07 2005

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