Re: cyanotype question
Oh Henry....
(sounds like a candy bar) First let me answer your question: because I read
in Ware's book that Herschel first used just pot ferri, I was surprised that
THAT was sensitive. Thus my goal was to see how little of FAC I could use.
I always keep FAC at a 20% and pot ferri at an 8%. So I kept the pot ferri
constant.
But maybe I should do what you do, below.
NOW, where the rubber meets the road. Yesterday I did a bunch of prints on
Fabriano AEW with the new formulation 1A+6W+7B and it just is TOO slow for
me to use in practice on sized Fabriano. I ended up having to expose it for
30 minutes on the sized paper when I usually expose for 5-10! It is smooth,
and it is paler, but not that beautiful turquoise that you get on Platine or
Weston (which actually I can't expect on alkaline FAEW anyway). So what I
have decided essentially for the underlayer on FAEW sized is to stick with
either a 1A+1W+2B or 1A+1B. But for a straight cyano print the tonal range
and smoothness of the dilutions is really beautiful.
If I were to use Rives BFK this would not be an issue as BFK is very good,
or at least has been in the past very good, with cyanotype.
Also, Sam was testing on different papers at the same time that I was, and
at 50% humidity thereabouts, and hopefully he will report his results on the
list. We have definitely agreed that a lot of these results are so paper
dependent.
Back to square one with a gum underlayer, though, because doing 6-9 prints
at once I really cannot have a 30 minute exposure time. I'd never get
finished.
Chris
__________________
Christina Z. Anderson
http://christinaZanderson.com/
__________________
----- Original Message -----
From: "Henry Rattle" <henry.rattle@ntlworld.com>
To: <alt-photo-process-l@usask.ca>
Sent: Monday, December 08, 2008 5:32 AM
Subject: Re: cyanotype question
Awesome, Chris! Thank you so much for the hard work and helpful
illustrations. One question - in my dilution tests, I just used 1A + 1B +
xW. Why did you decide to use B = (A+xW)?
Best wishes
Henry
On 7/12/08 18:03, "Christina Z. Anderson" <zphoto@montana.net> wrote:
LOL Charles,
Sam Wang and I have been laboriously doing test strips this weekend,
testing
cyanotype stuff back and forth (when I really should be reading and
grading
30 papers). I just got my 3 new 4x5 step wedges (31 step) from Stouffers
so
I can do three tests at a time which is really fun.
I can blame Henry Rattle for this spate of experiments, or whoever it was
who asked the original question of getting a paler blue for a tricolor
gum
underlayer. And then Sam who began to test it this weekend.
Caveat: Sam is the cyanotype guy to be answering your question--he has
done
a ton of it and I really only use cyanotype in conjunction with either
gum
or palladium, the latter which I absolutely love.
But here is what I've been mulling over: I went to my Mike Ware
Cyanotype
book which of course, has all KINDS of info in it so I don't know why I
would have to reinvent the wheel. I do think the book is a must-have for
those who do cyanotype all the time. Every time I read it I find new
information again.
He has a very interesting chapter on the different formulae in existence
since cyanotype's beginning. And what surprised me was that Herschel
originally started out with JUST pot ferri!! It was quite slow so the
practice of adding FAC began.
So then I thought, what happens if I increase the pot ferri proportion
etc.?
And water as well?
The formulae historically range from 2%A20%B to 20%A2%B, btw. Thus why
cyano
is such a forgiving process. I think you could just dump a teaspoon of
each
in a cup of water and still get a good print!
Sam and I both seem to agree that the more B the slower.
My conclusions from this weekend are that I will, from now on, dilute A
way
down when using it for tricolor gum. BUT it could be this way in MT just
because the water enables the solution to better hydrate and sink into
the
paper surface, so maybe it does not have the same good outcome in a humid
environment? And I think you live in humidity?
Anyway, here are my tests on Platine and FAEW:
http://christinaanderson.visualserver.com/Text_page.cfm?pID=2076
I'm a bit hesitant to draw immediate conclusions and give you my opinion
on
your question, below, but what I am finding is that the smoothest coats,
and
the palest blue perfect for tricolor, come with extreme dilution of the
mix,
which both Henry and Sam agree upon (dilution of 7x!). So my GUESS to
your
question is that the more you add of the FAC the less smooth it may
become.
You can see that the graininess and the bleeding occur on the increased A
test wedges. All of my step wedges without added water are grainier than
the
ones with added water on both papers. BUT that is at 66 degrees and 23%
humidity in Montana which may be skewing these tests, so if you find out
anything could you post?
Chris
__________________
Christina Z. Anderson
http://christinaZanderson.com/
__________________
----- Original Message -----
From: "Charles Ryberg" <cryberg@comcast.net>
To: <alt-photo-process-l@usask.ca>
Sent: Sunday, December 07, 2008 10:31 AM
Subject: cyanotype question
Folks: While struggling with the hassles of getting a smooth second
coat
on cyanotype it occurred to me that I could just double the strength of
the solution--40 grams instead of 20 FAC in 100 ml water. Has anyone
ever
tried this?
Thanks Charles Portland Oregon