Re: outdoor gum demo
Yes.
On Apr 17, 2009, at 12:34 PM, Alberto Novo wrote:
it's very interesting that greenish brown/brownish green/brownish
stain
color is pretty effective at blocking UV (visible light DR and UV
DR is
different) for pyro-developed silver/gelatin negatives, whereas
"coincidentally" green color is the strongest UV blocker for many
inksets
/ printers. Two most different medias (printer ink / stained gelatin)
exhibiting similarities in the same context -> confusing indeed.
IF the UV absorption is extended in the visible range,
THEN
there is some absorption *also* of the blue radiation, so that
chiefly yellow is transmitted (brown is a dark yellow).
BUT (not a logical variable :-) )
this is not a universal rule (again, think to sun oils...)
Not that I'm interested in pursuing -> just mentioned for the
records...
:^)
Alberto
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