On Sun, 18 Jan 2004 Ender100@aol.com wrote:
> So, you are saying that humidity combined with heat will fog and stain? Do
> you know which of the two is the culprit? It's easy to control humidity and
> heat seperately in an enclosed environment such as a coating room with the
> door closed. Perhaps cool, humid conditions are different. Hey, let me know
> how those tests come out :)
OK, you tell me... I find that in the summer when it's very hot and humid
(closing in on 90F indoors... I hate air conditioning and always resist it
until things get unbearable, and that's the moment), a gum print has to be
exposed nearly as soon as it's dry (between 15 min & a half hour probably)
or it will show so much DICHROMATE stain I have to use clearing bath...
If I expose promptly it's OK, and as soon as I turn the air conditioning
on it's OK too.
I'd guess it's not just heat or just humidity but the two together... on
the other hand, I don't get that kind of humidity without the heat. So I
don't think it is possible to "separate." At least not in NYC, where they
say,"it's not the heat it's the humidity," but they never say that when it
isn't hot.
> You said some people feel it is easier to coat with wet paper, though you
> found it stained more—did they find the same, or did they continue to prefer easy
> coating over stained prints?
Mark, I don't "know" anyone who's done that... I've READ it. And frankly
I suspect that maybe one person in the whole world since Fox Talbot ever
did it and everyone else copied from them... And I'd make a distinction
between *humidifying* the paper, which Keith does, and WETTING the paper,
I mean WET paper ! That would sure upset your precious gum pigment ratio
anyway, probably adding about 50% more water per square inch (or
centimeter.)
J.
Received on Sun Jan 18 21:54:51 2004
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