Re: spots and dots and other gum stuff
Chris wrote.... .... I came across a fun and thought-provoking quote that might sum it up for you: from the Photo Beacon 1904, a Mr. Warburg:Was this Warburg an Englishman? I saw a couple of his prints from about that period somewhere in Londan, possibly the Victoria and Albert. They were WONDERFUL ! In fact I saw one for sale at a reasonable price. (Why didn't I buy it??? Damn !) Still, in my tests, the gum coating was less sensitive when still damp than when fully dry... tho that business about not being light sensitive when wet is easily disproved. (In fact if I recall correctly Mike Ware said that already.) He hastened printing by placing damp paper behind the sensitive paper! "For it is not true that it is necessary for gum bichromate paper to be quite dry in order to be very sensitive; and it is also untrue that the moist coating in insensitive. The paper is most sensitive shortly after coating, when the gum bichromate film is no longer sticky, but the paper is still damp. Further drying diminishes the sensitiveness, but dampening the paper again increases it. This variation in the sensibility is so considerable and noticeable that it is curious it should not have been recognized and used long ago." Warburg says he printed for 6 or 8 years with an actinometer and measured all this stuff. Judy, the dreaded titration gum stain test that Koesters originated is repeated in the Photo Beacon of 1906. So it went from Germany to England to America....in this day and age of instant info I am surprised at how slow news of trends flowed back in the day.What you mean "dreaded." I consider it an old "friend," like "el tigre" our honorary title for the alley cat that arrives at odd hours, day or night, to serenade the neighbor's lady (cat)... But whence the term "titration" --? Is that theirs or yours? As part of an accidental "new year's clean up" I went through some of the spate of "health" & "nutrition" newsletters that keep arriving in the mail... their seeming mission (besides extracting $39 from me) being apparently to correct endemic myths about diet, exercise, weight loss, sleep, gastric reflux, gastric reflex, vitamins, food supplements, minerals, etc. Which is to say, apparently most of our belief systems can be disproved by controlled placebo testing... And that's today, with the internet, labs, peer review, the FDA, MDRs and Mayor Bloomberg. 100 years ago there were no such controls. It's a miracle they got anything right. Judy.
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