Re: Dark reaction
On Mon, 2 Nov 2009, etienne garbaux wrote: Hi Etienne... Of course, as we say in Greenwich Village, "chacun a son gout," but I suspect that we have so many variables here that firm conclusions are risky. For instance, your comment makes me think that there's really no such thing as "fluorescent lights" -- but probably 10 different kinds (eg. black light fluorescents, & some other kind my neighbor was using (as I recall "blacklight blue"), plus plain vanilla "regular" fluorescents, and probably every few years a change in "state of the art" -- In my own experience, not only differences in the actual colors of the light and the starters, but differences in the bulbs as well. For instance, we have only 8-foot fluorescents throughout our 2-floors.... except for the shower & a couple of other places where there's no room for a long tube). I put them in when we did the original unwrecking job, 50 years ago. At the time, folks said, "yuck, they look so commercial," but I always loved them -- AND, I figure we've saved something like $25,000 in electricity bills, because the layout of this 200-year-old "row" house is long & narrow, like a messy bowling alley, so you need a lot of electric light even at midday. But this long windup leads to the fact that last summer, for the FIRST TIME one of those bulbs burned out, and so, big deal... we bought a new one. But THEN, uh oh, it turned out that the new bulbs were fitted to a different starter (or whatever they called it) so they buzzed and flickered... until, long story shorter, we located a factory in New Jersey that shipped a case of 8-footers that work with our fixtures to a store on 14th street for us -- so we hope we're set for the next 50 years,,, All of which is a long way of saying, who knows? I have no idea whether these bulbs would fog gum (they never have in the studio), nor do I know what kind of fluorescents those bulbs in our class ceiling might have been.. (I always figured they were just "fluorescents")... However I do know that gum really is so flexible that that level of "fogging" could have been incorporated into our procedure... that is, just a somewhat longer soak. (We coated by the fluorescent light but had a drying closet with only a red safe light.) But PS. What "dichromated gelatine" process do you use Etienne? What's it called for short? Judy Judy wrote:I have however come across warnings against fluorescents in "the literature," but wonder if the warners ever tried it. As I've probably mentioned, when I was teaching "non-silver," the classroom (a repurposed chem lab) was lit by several banks of fluorescent lights set in a fairly low ceiling.I coat and/or sensitize gelatin-based dichromated processes by red (lithographic) safelight, after proving to my satisfaction that the gelatin-dichromate processes can easily be degraded by fogging even under bug lights or low-wattage incandescents -- but, as I've said before, I don't use gum, and what is necessary for dichromated gelatin is not necessarily required for dichromated gum.
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