Re: New Cyanotype

Judy, happy for you but ... blue water is a standard issue for me (I double
coat). That's why I'm overexposing my cyanotypes incredibly - I never
understood the "expose for highlights becoming one - one and a half stop
darker than what you want in the final print" suggestion... If I do it that
way, I get empty highlights, highlight-like midtones and weak shadows. But
if I expose the print until the shadows are completely reversed, midtones
reversed but less than shadows and highlights blue (zone IV I'd say) then I
get the print I want (after the print turning the first development tray
dark green/prussian blue - 2 mins - and the second one very weak cyan/aqua -
2 mins - and clear in the third one - again 2 mins). The only case I hadn't
blue water was when I was adding gum arabic (4 drops to 20ml sensitizer) and
10% potassium dichromate (2 - 3 drops to 20ml sensitizer) to the emulsion.
In that case the shadows would look almost whitish in development and won't
dissolve in the development water (in my case, it's mainly the dissolving of
shadows that makes the water prussian blue) and sometimes it would convert
to deep blue in peroxide bath only, not before. And yes, my paper's not very
absorbent - I had best results adding 2 - 3 drops of ILFOTOL to 20ml
sensitizer (that's a wetting agent similar to Photo-Flo) - but I don't see
any puddling when I coat; the paper gets matte in one to two mins. BTW, I
use 0.1% citric acid as developer (1gr to 1lt) in order to compensate -
maybe - alkaline wash water (not scientific, I didn't even try to measure
the PH of our tap water - what I know is it stinks chlorine!).

Regards,
Loris.

----- Original Message -----
From: "Judy Seigel" <jseigel@panix.com>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Wednesday, May 19, 2004 8:46 AM
Subject: Re: New Cyanotype

> ...
> Christina, I notice that you say "the complaints about the traditional
> (old) process are....", but you don't say you have observed these things
> yourself. I have made hundreds of cyanotypes, and taught airhead
> undergraduates who must in the aggregate have made thousands more-- and
> NEVER seen the Prussian blue wash out during wet processing except in two
> circumstances:
>
> 1. When the emulsion is too fresh.. I don't mean A&B freshly mixed
> together, but when the A & the B themselves have not aged enough. I found
> that two hours old they washed off about 60%, after that they washed off
> successively less. Until about day 3, or maybe 4, no washing off. That
> is, no "blue water." However, the top visible step of a freshly exposed
> but not yet developed print does drop down 2, or 3, or more steps in
> development. I don't know if New Cyanotype does that, but you can easily
> allow for it in exposure. (And that makes green not blue water.)
>
> 2. When the paper is not absorbent enough or too much emulsion is sloshed
> on. Look at the freshly coated paper at an angle -- if you see puddling,
> it will wash off after exposure, often leaving white spots.
>
> Perhaps alkaline wash water has this effect, but I do not believe it is
> intrinsic to the medium. I have also NOT seen those "stained highlights."
> except where the negative was too thin.
>
> Judy
Received on Wed May 19 01:28:08 2004