lst21 at cam.ac.uk
Wed Jun 19 09:00:48 EST 1996
Paul has it right.
Keeping the gel at -70 is necessary if you use preflashing, and for some of
the fluors to work efficiently.
Some confusion can be caused when you come across a cassette that has 2
"built in" screens, one on each side. These are designed for use with
external X-ray sources, not for exposing gels. They are a big waste of
money unless they are "borrowed" from your local X-ray department.
Your first careless encounter with single-side emulsion film will be enough
to convince you of the limited penetration of S35 - screens or no screens.
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