It is definitely more difficult than platinum, if you are familiar with
that one.
Those who are expert at it (or who think they are;-)) will tell you it's
easy. In many ways it is, once you've managed to overcome the initial
hurdles. The process has *physical* problems that platinum, for instance,
does not have, like air bubbles coming through the gelatin, and then there
is frilling, and then there is reticulation and then...
It seems that beginners somehow have to experience these problems and then
suddenly, for those who are persistent, the problems go away, and beautiful
prints can then be made.
On the other hand, from a chemistry point of view, carbon is more
predictable than platinum. The pH of the paper, if you are using paper,
does not seem to matter at all. And of course, you can print on anything
relatively waterproof, like glass, plastic, ceramic, etc. If you are not
happy with a print for any reason, just use a sponge saturated with hot
water, and wipe the image right off its support. The same support can be
used again. I used to do my tests on white plexi, which I would use over
and over.
Carbon is also more finicky about room temperature and humidity. In the
North Eastern part of North America, you can pretty well write off July and
August as active months unless you have a very powerful air conditioning
system. I gave up using it commercially during the summer months, years
ago. On good days, when temperature was below 22C the process worked well,
but this depended on the nature of the gelatin.
Carbon is certainly more difficult than platinum but it is certainly
manageable and the results are worth the extra effort.
I don't know if we still have an FAQ for this list. Perhaps someone else
can help?
Luis Nadeau