RE: GUM PRINTING QUESTION

On Mon, 8 Aug 2005, wcharmon@wt.net wrote:

> .... My vote
> would be for stating loudly the gum printers motto: "It depends"

My information & experience is -- exactly ! I recall that Sil Horowitz,
chemist, said that there is no risk to archivality from residual
dichromate, as it's already oxidized (or like that). I also recall reading
in old gum articles that a printer would deliberately use residual stain
for added depth in tone.

The belief in necessity of clearing may have been a holdover from silver
printing, or maybe at the time it was albumen printing, when it was found
that incomplete or faulty clearing compromised the tone in time.

I've found "it depends" on the weather, too. I remember a series of prints
done in hot humid NYC summer when I was resisting the air conditioner had
such an exquisite golden (dichromate) tone over all I tried repeatedly to
match it with a yellow over-layer. Didn't work.

As for what "Livick says": Livick is an astounding expert in his own
methodology, but his knowledge of dichromate chemistry is, um, iffy. There
are several miss-statements in that respect in his book (not to frighten
the horses, of course -- so forget I said it, OK?)

Judy
Received on Mon Aug 8 23:46:38 2005