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Plain chlorine bleach
----- Original Message -----
Sent: Saturday, October 31, 2009 11:33
AM
Subject: Re: Gumoil
regarding gumoil:
if i remember corrctly (it's been sometime
since i did the reading about gumoil) the process uses bleach, i think karl
koenig says "ordinary household bleach". since american and european bleaches
are most likely different or at least the brand names are. what's the chemical
in the "household bleach" that is the one used here? or will any kind of acid
(anything with a low ph) work?
most people will already know this, but
there is a video tutoral from karl koenig online:
Paul
Viapiano schrieb:
000d01ca5a54$99e38d20$7000a8c0@dell4600 type="cite">
Thanks, Christian & Jim...
In a Camera Arts article, Karl mentions a more
contrasty positive but more washed looking out as well. I didn't get what he
was after there.
I experimented with my normal gum neg inversed
to a positive...but was wondering if anyone had a suggested DR.
It doesn't matter, I'll be testing
anyway.
Paul
-----
Original Message -----
Sent:
Saturday, October 31, 2009 12:42 AM
Subject:
Re: Gumoil
Paul
Jim help me to get succes in this process. I am just thankfuf
to him. The choice of the paper is a great part of the succes , lana
aquarelle and Fabriano give great result. There is o pigment in your
coat so exposure will be shorter. and the exposre will be
different as you must use a contrastier negative(positive) compare to your
gum negative
christian nze Give it a try, Paul, and see what happens! I
don't know the answer, so I am not trying to bait you ;) And I do not
think that it is 3:1....1 pt of gum, mixed 1:1 by vol, plus 2 pts gum
mixed 1 pt gum(powder) to 2 pts H20, plus 1 pt saturated Potassium Dich.
This serves as a good starting point, and is what I use. Depending on your
results, you can coat your surface, after it has dried, with a second
coat. Your exposure is going to be longer...4.5-5 under Black light or
sun. Do a few test prints as it can be very tricky!
On Fri, Oct 30, 2009 at 10:45 PM, Paul Viapiano
<viapiano@pacbell.net> wrote:
I know that Karl Koenig uses a 3:1 gum/pot
dichromate ratio for printing the positive, but I was wondering if
anything would be amiss should I use my usual 1:1 (sans pigment, of
course) since my gum negs are tuned to that already and I have a known
exposure factor...
3:1 would make for a more contrasty gum
deposit, I would guess but I'd have to expose longer than my 1:1 mix,
right?
Someone, maybe Katherine (?) had a rule of
thumb for exposure times with differing ratios/amounts of
dichromate...?
Thanks...Paul
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