U of S | Mailing List Archive | alt-photo-process-l | Re: Measuring humidity

Re: Measuring humidity



On Sep 28, 2006, at 8:41 PM, Ender100@aol.com wrote:

Katherine,

Temperature certainly is a variable, but my home is 70 degrees year round and it's the humidity that can vary a lot. Humidity has a LOT of influence—at least with PT/PD. But then, as you say, I am holding my temperature constant—and wearing the same lucky undershorts

I guess I didn't make myself clear; I didn't mean that humidity doesn't have an influence; it should be clear from my earlier post and my posts over time that I think humidity is very important; higher humidity makes for faster printing and easier coating, for example. When I say "it's not the humidity, it's the heat" I'm answering people who say high RH creates problems for gum, makes it "not work," produces that spontaneous hardening that has been plaguing you so much. My point is that obviously it's not true that it's the humidity that's causing the problem, as I print in very high humidity without these problems, and Keith's post also confirms that humidity is not detrimental to gum printing. Hence my comment that it's not the humidity by itself that's the problem, it's heat added to humidity. Keep those shorts on,
Katharine