one more mordancage post, long...

["Christina Z. Anderson" <zphoto@montana.net>]

Cor,
     I think I may have found an answer to your problem of not liking the
yellowing of fiber papers!
     Today I did my final (yeah, I've said that before) testing on
mordancage.  I tested 40v, 20v, and 10v hydrogen peroxide.  I tested doing
the process on fixed prints, unfixed prints, in room light, under safelight.
I tested Ilford glossy MGIV, Ilford warmtone, Oriental (old, fogged), Agfa
MCC, Ilford Matt, and Forte polywarmtone glossy--plus Oriental RC and Forte
polywarmtone RC.  I'm a mess, I stink, and I have little bits of emulsion
everywhere--but I found out what I wanted!
     What I found is that yellowing was greatest 1. with the highest
strength peroxide (!)  2. on fiber paper 3. doing the mordancage under
regular room light  4.with not fixing the mordancaged print upon completion.
When I did the mordancage under safelight with less strong h.p and fixed
before having the print hit room light it did not yellow.  Try it for
yourself and prove me right :)  Wash your print thoroughly before fixing
tho, because it stinks to high heaven when the print hits the fixer with any
mordancage solution left in.
     Nate--for you, I found out this.  For some flukey reason, sometimes a
print doesn't work.  Then the next print (same paper, same printing session)
does.  I thought maybe, as you did off list, that a print that didn't work
was somehow selenium toned and I just didn't realize it.  I do find that
selenium toned prints do not mordancage as well, but an occasional print
doesn't make it either for no reason.  But Shultz had said in his Shutterbug
article that the age of the paper affects whether it bleach etches fast or
not, and the Oriental paper I used that was old and fogged did not budge in
the mordancage so there could be truth to what he says. Hence I would
tentatively say selenium toned prints and old paper are tough, until I prove
myself otherwise.
     I've simplified the process to be user friendly:  2 T. of copper
chloride and 80ml of glacial acetic; mix in a liter of water in that order.
Then equal parts of h.p with that.   No hauling out the scales.
     I've also found that it is immensely better to start with a dry print
than a wet; less time to infuse the chems.
     According to Neblette the h.p does the softening of the gelatine, the
copper chloride does the changing of the metallic silver to silver ions.
This is why the stronger h.p. veils the emulsion--it really destroys it fast
and furiously.  I think this is also why the stronger h.p makes the print
yellower--it softens the gelatin too much so that in developer it absorbs
too much and stains, especially when not fixed.
     I used dektol mixed normally--1:2.  I did not find any reason to dilute
the developer.
    Why i tested three kinds of h.p is to see if the 3% drugstore type did
make it.  That is about 10v.  It does work, albeit slower, but I had to rub
quite a bit to get the emulsion to flake off.  It does not "veil" the
emulsion off as the stronger volumes do.  Rubbing off the emulsion was
simplified with a plastic scouring side of a sponge.  But I found that
sometimes the 40v removed too much emulsion and I think I may prefer 20v
from now on, especially because of the yellowing issue.  Somewhere around 20
I did not notice yellowing, but how close to 40 I could get I do not know.
     I also tested the mordancage sabattier--1.develop an exposed print  2.
rinse  3. mordancage  4.rub off emulsion under room light 5. redevelop.
It's OK--you essentially get a black and white negative image which has its
uses...
     I also found Ilford paper consistently mordancaged well; Forte did well
most of the time with an occasional fluke, as did Agfa, and Oriental.
     RC paper does stay nice and white but the emulsion comes off so readily
that you can't really expect a veiling thing to happen and stay put unless
you are so very careful and don't wash, etc...
     Enough said,
Chris