Re: pyro and cyano
Bob,
I quit using the hydrogen peroxide because it was questioned to perhaps
compromise the archivalness of the paper and it was unnecessary because the
print would eventually get to that dark blue anyway, PLUS it seemed to
bleach the print a bit, though this latter is only subjective to me and
another person or so.
BUT this is my question--does the hydrogen peroxided print actually get
darker blue than one that oxidizes over several days? So if it gets darker,
there would be a benefit to it. I have not tested this.
And who the hell cares about the archivalness of my prints--like I'm going
to be famous one day????
Let me tell you, people complain about gum being fickle, I find personally
in my practice cyanotype the most fickle process of all. I can only chalk
it up to the fact that humidity and coating plays a way greater part in that
process than people imagine. I know Sam Wang tames it beautifully.
I also find that it is very unpredictable with my students in literally
every class I have taught on alt. Yesterday, one student used the same neg
and curve and the print was completely overexposed and unusable. And I know
he is not a student that would leave the lightbox on and go out for a cup of
coffee.
But I am always combining cyanotype with another process, either gum or
palladium, the latter which I just love so I actually use it frequently. I
think I just need to really delve into Mike Ware's book.
Chris
__________________
Christina Z. Anderson
http://christinaZanderson.com/
__________________
----- Original Message -----
From: "BOB KISS" <bobkiss@caribsurf.com>
To: <alt-photo-process-l@usask.ca>
Sent: Friday, April 10, 2009 8:06 AM
Subject: RE: pyro and cyano
DEAR CHRISTINA ET AL.,
Does using the hydrogen peroxide cause any problems during
processing or after? I use it because it gives me the final depth of blue
quickly so that I can judge if I have the correct exposure.
CHEERS!
BOB
-----Original Message-----
From: Christina Z. Anderson [mailto:zphoto@montana.net]
Sent: Thursday, April 09, 2009 11:22 PM
To: alt-photo-process-l@usask.ca
Subject: Re: pyro and cyano
Chris, when you say "six stops"
--- how many steps on the 21-step is that ?
Hi Judy,
6 stops is 12 steps on a 21 step tablet (1 step=1/2 stop) or 18 steps on a
31 step tablet (3 steps= 1 stop). This is why I don't talk steps because
it
is confusing with whether one is using a 21 or a 31 or a 44, but a stop is
a
stop is a stop.
Yes, cyano gets darker as it oxidizes. I never use, and never recommend,
hydrogen peroxide because eventually the print will turn that nice darker
blue anyway.
Chris
(If I display ignorance,
please excuse.... But I live in a 21-step dimension, not a "stop"
dimension. In fact when I strayed into the wet darkroom last month on a
different mission, I couldn't even make the safelight go on !)
In any event, my rule of thumb for an average neg in simple cyano was 8
or
9 steps, tho I found many ways to modify that. For instance, pages 34
thru 37 of Post-Factory #5 ("Managing the Blues") show differences from
light source (sun vs. UV bulbs), paper (Strathmore Artists v. Whatman
Fine
Print, among others) proportions of parts A & B (as discussed on this
list
by... Sandy?, Bob Shramm?, others ?) a while back; time on the paper
before exposure, delayed development, double coating (according to
paper),
acid "prebath" ("tends to extend and deepen range very dramatically"),
etc. etc. etc.
That issue is dated "August 2000", so (BELIEVE ME !!!) I've forgotten the
details (the above is from a quick skim... but I'm not printing cyanotype
these days, and need that disk space ...ie, what's left in the brain ...
for current endeavors, so am TRYING to stay away from this topic... Tho,
since you insist.... my eye lights on mention that, to my surprise, I
discovered that "dry down" in cyano, goes on, not just for one day, but
several ... But you knew that ?
There are also 21-steps A through D2 of various ranges & why (p.37). But
as in "devil get thee behind me," I change the subject: Another P-F (from
around then) shows a "Cyanodyke" -- what the photographer called her
vandyke brown prints over cyanotype. The print was very pretty, with nice
combined tones (tho in repro b&w only). As I recall, she didn't mention
bleaching, tho of course in the other way around -- cyano over vandyke
brown -- the silver gets bleached by the potassium ferricyanide in the
cyanotype. A short item, but if I locate it, I'll cite.
Judy
not suitable for cyanotype as it is for other processes that have longer
tonal ranges, unless one were to contract the tonal range of the pyro
neg
to match cyano--or have subject matter that is tonally contracted
anyway.
BUT, and this is my question: does anyone know the maximum DR possible
in a pyro neg? I do not have a UV densitometer. And, from memory
(which
obviously doesn't serve me too well so please answer this, too) a film
negative can actually record up to 13 stops of info, pt/pd about 10, BW
paper about 7, and cyano about 6...you get my point perhaps.
[CUT.....]
http://christinaanderson.visualserver.com/Text_page.cfm?pID=2448
OHHH man do I need to get back to work, this is too fun posting all
these
silly visuals, and hopefully someone will benefit except me :)
Chris
__________________
Christina Z. Anderson
http://christinaZanderson.com/
__________________
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