Top down again?, was Re: Learning, loooong post

OK, here is the thing. I strongly believe that the hardening in gum
is top down But I was too assertive in expressing my position and
appear to have offended a couple of persons. So I have attempted to
communicate with those persons to express my regrets.

However, I would also say that some people may have misunderstood
what I meant. I tried to make it very clear that there are many
things about gum printing we don't understand. The mechanism of image
making is really completely wrong, in theory, yet people manage to
make very nice prints in spite of that. As someone who has worked a
lot with gum, I understand very well that we can not explain
everything about the formation of a gum image by the top-down
concept. I also understand that there are few, if any, practical ways
to take advantage of top-down hardening.

However, some attempts have been made to take advantage of the
top-down concept, and are described in the literature. I have, for
example an article published in French from the 1920s that describes
an elaborate system of gum transfer, which obviously assumes top-down
hardening.

However, quoting ancient references and authorities is something of a
waste of time when there are some fairly easy tests that one could
run to test the concept.

Sandy
Received on Sat Apr 8 14:55:35 2006