tooth and no tooth

> gdimase@hotmail.com wrote:

>> Glass and alluminum are perfectly clean without any "tooth" and you can
>> print perfectly on them, right?

I haven't heard of anyone who can print gum on a hard surface without a
substrate or some kind of roughing up. If I remember correctly, Galina
uses gelatin.

And I daresay Christopher James is right about ways to get "tooth" on
those impervious materials... HOWEVER, I think the business about "tooth"
being needed on paper, needs some qualification: It's quite possible to
make a reasonable gum print on a smooth paper (I've used for instance a
Strathmore plate finish drawing paper). Odds are the highlights will wash
off, so unless you take steps it won't be full tonal scale -- but probably
about 75% of the image will arrive.

And, (drum roll please) the story about gum hanging onto the tooth in
*paper* is another one of those Anderson fairy tales... exactly like the
great GPR test (oops I said it again). Anderson decided it was *logical*
and never checked it against a control, drew this scientific-looking
diagram, which in due course was copied from Dudley & Henney into Keepers
of Light & I don't remember where else, but I've seen it here or there.

I don't think this is one of the great mysteries of photography either: On
paper, even with no tooth, the gum solution soaks into the paper fibers,
and so, instead of sliding off (as it would from a hard, entirely
non-absorbent surface) it makes a print. In fact I think a pretty fair
print with some rudimentary highlights can be gotten -- it's years since I
tested it and there seemed little reason to continue -- but, facts is
facts.

Judy
Received on Sat Nov 13 00:54:28 2004