Re: dichromate stain

OK, after this post I am going to go to Dichromate Stain Anonymous...

I am hysterical (laughing, not crying, yet, anyway) at the moment; here I
sit, reading the BJP, and in the 1870's they were discussing the same types
of things!!!!! Actually, from the 70's to the 90's, twenty YEARS and they
disagreed! I have no hope for us :) But at least it was in reference to
carbon printing and not gum.

I have to add **one more variable** (don't you just love it?) First, IMHO
even tho Keith's well water is heavy in iron and he gets no stain does not
disprove that iron contributes to stain; it just says that given all the
other variables Keith practices in combination, iron does not contribute for
him. It may still be the variable that Clay experiences. So none of these
variables is down the drain, including Katharine's light source theory.

We could even add subjectivity as a variable in here, too--how much stain is
perceived/perceptible, for instance. In any case:

In ref to continuing action, now (where a print has received SOME exposure,
I know I know, different than dark reaction but the following **may** apply
to dark reaction as one other variable) when it first was observed, some
said it was a myth, some said they were able to utilize the continuing
action to their advantage by exposing half the time and letting the paper
sit 18 hr, etc. etc. Argue, argue, argue.

Finally all agreed that heat, humidity and age were contributing factors,
after the first number of years of denying continuing action actually
existed. Kosar also seems to prove this.

Then one more variable was suggested: discussed by Foxlee in the 90's, he
suggested increased oxidation as being a factor, presuming that oxidation of
the chromium (help me here, chemists) was initiated and created the
insolubility; In other words, does air circulate freely around the paper or
not. He was able to store coated and exposed paper in dry, dark, unaired
conditions for 185 DAYS and get a perfectly exposed print. Hmmmm.....

OH, and I'll add one more factor, drying prints in subdued room light, not
the dark (which would probably contribute to continuing action, not dark
reaction technically, but may factor into stain).

Just for the record, I'm reading this WHILE developing 6 cyanos in my
bathtub WHILE writing this post. And Kerik, I've gotten rid of the lavender
highlights by a citric acid soak (don't have oxalic...yet).
Chris
Received on Wed Jun 16 10:50:04 2004