Re: gum question
BTW, a tip (this was very useful to me) can be: If you (absolutely) want nicely calibrated negatives suitable for gum, just calibrate for cyanotype on your usual paper (the one that you use for pt/pd or argyrotype - if you already don't do cyanotypes, that is) and use those negatives for gum. You'll just have to adjust your coating solution / exposure and development according to the negative. Sounds complicated but believe me it's much easier that way! (Pretty effective and successful too.) Just pay attention to not exceed 14-15 steps in the 31-step tablet with your cyanotype sensitizer; over that (log 1.5 DR), it's a little too strong to work comfortably with gum. I currently use 2A+1B trad. cyanotype, and it gives me exactly 15 steps (including dmax and paper white). Those cyanotype negatives print gum very nicely. I always had better results (due my particular working style and/or materials?) with weak sensitizers; I use only two dichromate strenghts 5% and 2%. (AD, 1+1 gum/pigment+dichromate.) I also have 10% on hands for unusual situations though. Regards, Loris. 28 Mayıs 2009, Perşembe, 12:50 am tarihinde, Paul Viapiano yazmış: > Loris... > > Yes, like a painter. I'm so glad you said that... > > I'm experimenting with one-coats and gum-overs...learning much on every > exposure. > > Taking notes, as I always do, even for silver prints... > > When I have something to show you, I'll post a link. > > Thanks for the reply...much appreciated. > > Paul > > > ----- Original Message ----- > From: "Loris Medici" <mail@loris.medici.name> > To: <alt-photo-process-l@usask.ca> > Sent: Wednesday, May 27, 2009 2:04 PM > Subject: Re: gum question > > >> For stock gum/pigment solutions I do as you describe, in case of adding >> pigment from tubes I use 1 part dichromate to 1 part of gum + the >> pigment. >> (I tend to use strong pigments in small amounts, therefore I >> assume/accept >> both working styles as being equivalent.) The pigment amnt, exposure >> time, >> dichromate strength, development time/method all will change relative to >> each other and most importantly to your goal for that particular layer. >> It's not rocket science at all; just try to establish "the feel" by >> experimenting (changing only one variable at a time) and good note >> taking. >> Don't try to work by numbers only, it's counterproductive and boring >> (you'll understand what I mean if you try to calibrate gum). Try to work >> more like a painter, you'll see that it starts to become (or, better, >> the >> general direction of your working style will be) second nature after >> some(!) experience. ;) (Not that I'm implying I have lots of >> experience...) >> >> Regards, >> Loris. >> >> >> 27 Mayıs 2009, Çarşamba, 11:38 pm tarihinde, Paul Viapiano yazmış: >>> If I premix gum and pigment together, would I still use equal amounts >>> of >>> that mixture and pot dich to make a 1:1 solution? >>> >>> Do I need to account for the pigment being already mixed in there? >>> >>> Thanks... >>> >>> Paul >>> >> >> >> > > > >
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