The process cannot be automated. On the same print you always use different
concentration of sawdust for different areas of the print at different
moments. For instance, a thick concentration at the very beginning and a
thin concentration at the end. As a rule, a thin concentration gives more
contrast. Some highlight areas may require a thin stream of water/sawdust,
etc. It's wonderful for monochrome work, especially since it is done in
practically broad daylight but doing this in 4 colors... And as with many
processes the prints get darker after drying.
>>> George's 4-color carbon process (I have seen many of his prints) is a
> simplification of the old double transfer tricolor process. He makes his
> own color seps off a scanner (he's been doing this professionally for
> years) and he makes his carbon tissues from scratch using liquid
> dispersions, thus avoiding the mess from grinding, etc. He may want to
> elaborate on the technique here but considering his 200+ pages of notes,
> let's say it's not for those of you who find cyanotype "challenging";-)
>
>Does he make this manual available?
I don't think it's a manual as much as a pile of notes. I may be interested
in publishing his method in a revised edition of my _History and Practice
of Carbon Processes_ which has been out of print for over a decade.
>>> I find his results are much superior to the 4-color Fressons, although one
> has to be careful with the word "superior" here.
>
>I take it that by superior you mean more controllable here. Is this the
>reason why you are not doing 4-color Fresson? that after some much trouble
>(in setup, coating, etc. etc.) the result is not that controllable.
I meant the overall look. Difficult subjects, e.g., motorcycles with lots
of chrome, etc. can be handled very well with Griffin's process. It's a
nightmare in color Fresson. I never used the color version of the process
because of its inherent lack of control. When my customers wanted permanent
color prints I used the double transfer tricolor process. The results were
the very best but the process was not feasible.
>>> Here UltraStable has an advantage as you can, with some extra work, use a
> variety of real papers. If you want on paper what's on your chrome, these
> are the processes to use.
>
>I would like to hear your comment on UltraStable from a technical point of
>view. From what I have read (from magazine articles or their literature), I
>have never considered UltraStable another (or a new) process.
It's unique as it is pre-sensitized and doesn't suffer from the darkening
effect and other variables in the dichromated version. I have seen many
excellent prints made by Bruhat in Paris and I have an excellent print made
by Berger in California in my collection here.
The UltraStable is obviously MUCH simpler than Fresson, the traditional
double transfer method I used to use, and Griffin's method. This said I'm
sure it's not entirely automatic and foolproof, especially if you use a
non-polyester base as a final support.
Luis Nadeau