Keith,
I checked Daniel Smith web site and they both list carbon black and lamp black, without using more detailed pigment nomenclature. My package says carbon black on it. It lists at $10.95/lb
Marek
> Date: Thu, 3 Jan 2008 09:17:26 -0800
> From: kthayer@pacifier.com
> Subject: Re: direct carbon or gum bleach development
> To: alt-photo-process-l@usask.ca
>
> Keith, it's somewhat confusing because "carbon black" is sometimes
> used as a general term to designate black pigments made from carbon
> and sometimes to designate a specific pigment, PBk7, which is why
> pigment numbers are so important. Lamp black pigment is PBk6; PBk7
> is called sometimes carbon black and sometimes furnace black and is
> sometimes given the marketing name "lamp black," but isn't actually
> lamp black. According to some sources, PBk7 is darker and
> velvetier than PBk6.
>
> I've been sick for weeks with a flu thing that turned into bronchitis
> and haven't got down to the workshop to continue my experiments with
> this. But because I'm still interested in exploring this, I wonder
> if you could say a little more about what's not working for you; is
> it "just" staining, or is it a problem with the bleaching too? Thanks.
> Katharine
>
>
>
>
> On Jan 2, 2008, at 7:41 AM, Keith Gerling wrote:
>
> > 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! Check it out!
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