Re: direct carbon or gum bleach development
Thanks for that advice. Just to clarify regarding the gum-over-silver: I was intending to use a different negative for the VDB - less contrast so as to fill in the image with warmth, and then overlay the shadows and details with the gum. On Jan 2, 2008 1:37 PM, Marek Matusz <marekmatusz@hotmail.com> wrote: > > Keith, > Seems like the cold train has arrived in Houston. Iit was chilly 32F this > morning. I have done a bit more printing this weekend (bleach developed > gums) with burnt umber pigment. Every time I learn a little bit more, which > means that mu failure ratio is not that hight now. Actually multiple prints > at the same printing session are very consistent, much more then traditional > gum. > > As far as some of your questions: lamp black and carbon black should be > colose to the same thing (or are the same thing). They are the very dark > carbon pigments. I am not quite sure about printing over VDB with such a > heavy pigment load. For one thing the gum image is so dark (in my practice) > you would not be able to see anything below it. Actually I have done less > pigmented mixes as well, so that might not be a valid concern. Of more > concern would be bleaching of VDB silver image during chlorox development > phase. You might try a test strip too see if the VDBgets bleached by > chlorox. > As far as papers are concerned I think that the bleach develop gum process > requires a very thin layer of gum that is anchored in a paper base. That is > the interaction od paper fibers and emulsion is critical. I accidentally > printed an image on very heavily coated paper (12% gelatin) and I got white > spots during development where the image just dissolved, mostly in > highlights. right now I am printing on unsized papers with most consistency. > > Marek > > > Date: Wed, 2 Jan 2008 09:41:18 -0600 > > > > From: keith.gerling@gmail.com > > Subject: Re: direct carbon or gum bleach development > > To: alt-photo-process-l@usask.ca > > > > Thanks Marek, > > > > Cold here in the midwurst and I'm staying put and making do with what > > I have at hand (which does not include Fabriano). But carbon black is > > the same as lamp black, correct? And I also have some pure graphite, > > and both of these stain what I've been using, which include Masa (as > > predicted by Loris), gessoed paper and wood, and the flip side of > > other gum prints on various papers (which, come to think of it does > > include Fabriano, albeit many times immersed in water, so it isn't > > like what you have used). > > > > Thanks for the offer. I'll play around a little more. The picture > > you posted was on unshrunk paper, correct? What impresses me the most > > is not so much the bleaching (without seeing a before-and-after it is > > hard to tell what that is) but the intensity, shapness and grain of > > the print (resembling, come to think of it, a Ralph Gibson...) What I > > would very much like to do would be to produce duotones by using this > > process over a Van Dyke print. What are your thoughts on that? > > > > Thanks! > > > > Keith > > > > On Jan 2, 2008 8:09 AM, Marek Matusz <marekmatusz@hotmail.com> wrote: > > > > > > Keith, > > > I have been using carbon black powder from Daniel Smith. Gum bleach > > > development requires higher density negative then normal gum. I would > say > > > something more like palladium negative density would be fine to start > with. > > > If you can email me a scan of your work I can perhaps troublesoot it. > > > Marek > > > > > > > Date: Tue, 1 Jan 2008 19:47:57 -0600 > > > > From: keith.gerling@gmail.com > > > > Subject: Re: direct carbon or gum bleach development > > > > To: alt-photo-process-l@usask.ca > > > > > > > > > > > > > > Hi Marek, > > > > > > > > My attempts look atrocious. What kind of pigment are you using for > this? > > > > > > > > thanks! > > > > > > > > Keith > > > > > > > > On Dec 20, 2007 4:05 PM, Keith Gerling <keith.gerling@gmail.com> > wrote: > > > > > Awesome, Marek. This is what I want MY prints to look like. Forget > > > > > all that multi-coat nonsense. > > > > > > > > > > > > > > > On Dec 20, 2007 2:28 PM, Marek Matusz <marekmatusz@hotmail.com> > wrote: > > > > > > > > > > > > All, > > > > > > More experimentation with gum printing and bleach development. > > > > > > > > > > > > I was intrigued by Loris's results with using unsized paper. I > thought > > > that > > > > > > it would give a rather bad stain. My tricolor gum practice > certainly > > > led me > > > > > > to believe this. However on numerous occasions I did observe that > > > edges of > > > > > > paper that I used which did not have gelatin size gave a darker, > more > > > > > > uniform black. SO last week I tried to use single sized paper, > fresh > > > and > > > > > > unsized Fabriano Artistico, and a throw away gum print that has > been > > > soaked > > > > > > over and over, but had a reverse side of Fabriano paper quite > clean. > > > My > > > > > > overall conclusion with this set of prints is that I liked unsized > > > paper and > > > > > > soaked paper best. They gave crispier prints. Perhaps this > technique > > > likes > > > > > > the gum to be tied up with the fiber of the paper and the bleach > > > development > > > > > > can give clear paper base. So I would advocate use of straight > > > watercolor > > > > > > paper, no need to size. I have not tried any other brand, but I > should > > > have > > > > > > some at hand and will try next printing session. > > > > > > > > > > > > I have also experimented some more with pigment density. I had a > more > > > > > > concentrated carbon stock of 3.75% carbon in 14 baume gum, that is > 50% > > > more > > > > > > then in my last set of experiments. The solutions are left over > from > > > dozens > > > > > > or maybe hundreds of experiments done in the last two years. Once > the > > > water > > > > > > dried out this would result in 3.75/0.27=14% carbon/solid gum > mixture > > > (I > > > > > > assume 14 baume gum is 27%). This is definitely black black. > Beautiful > > > > > > velvety matte texture of the deep black to take your breath away. > Scan > > > of > > > > > > the print here. This print was made on unsized Fabriano Artistico > > > paper > > > > > > > > > > > > > > > > http://picasaweb.google.com/marekmatusz1/GumBleachDevelop/photo#5145909559997921266 > > > > > > The mid tones are a little bit darker on this screen that in > reality. > > > Maybe > > > > > > even the two tones of black on the very edge are visible. Very > > > outside, had > > > > > > most exposure (I uped the exposure to 6 minutes from last time) > and > > > next to > > > > > > it is somewhat lighter edge from exposure through blank part of > > > transparency > > > > > > (Pictorico). This is a further illustration of how a fine tonal > > > gradation > > > > > > can be achieved with this method. > > > > > > I have also included an detail of the print scanned at 300 dpi: > > > > > > > > > > > > > > > > http://picasaweb.google.com/marekmatusz1/GumBleachDevelop/photo#5145909521343215586 > > > > > > Happy printing > > > > > > Marek > > > > > > > > > > > > > > > > > > ________________________________ > > > > > > Don't get caught with egg on your face. Play Chicktionary! Check > it > > > out! > > > > > > > > > > > > > > ________________________________ > > > Get the power of Windows + Web with the new Windows Live. Get it now! > > > ________________________________ > Don't get caught with egg on your face. Play Chicktionary! 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