Re: Cyanotype

Loris,

Loris said:
My point in using New Cyanotype is quite simple: I can get better dmax
(darker void black) with New Cyanotype, therefore more apperent contrast
(I come from silver-gelatine printing and sometimes miss the dark tones
I could get with FB glossy silver-gelatine paper). To get satistactory
dmax (this is a highly subjective issue; others may like the dmax they
get with Traditional Cyanotype, have absolutely no objection to that,
have seen many wonderful prints made with traditional formula even if
the dmax was not strong)

I would have to agree with you--the New Cyanotype is what I consider a navy
blue color, as opposed to the cyan blue of the traditional formula. I quit
using the New version because the traditional is the right color (cyan) for
tricolor gum, but I did like the color of the New a lot.

Loris said: with Traditional Cyanotype I had to coat the
paper twice. This was a real problem since there was 2x the risk of
abrading the paper (I can be pretty heavy-handed being a large person -
220lb, 6.22' - have ruined quite a lot papers while double coating...),
also "in my practice" traditional formula is more prone to
crystallization on paper "especially when double coating" (absolutely no
good for the sake of the image and the negative).

Question: which leads back to Michael, I think, who asked instead of using
20% FAC 2 parts to 8% potassium ferricyanide 1 part, why not mix a 40%
solution of FAC and then use that 1:1 with an 8% solution of potassium
ferricyanide...I wondered if mixing it up that heavily would lead to
undissolved FAC in solution, if there is a point where FAC falls out of
suspension....and then might lead to graininess or some such thing. You say,
below, you get crystallization on the paper--do you mean white spots, actual
crystals, graininess, etc??? Short of just mixing up a 40% and trying it
myself, which I might do, I'm just wondering if graininess that people
complain about with the traditional formula has to do with too much FAC...OR
even, if the amount of FAC doesn't even matter that much as one person has
suggested.

One other thing: anyone who bought my book there is an error in the
Cyanotype chapter, p. 64--the traditional formula of 20g/100ml is correct
but beside it, it should read "10 tsp" not 5. AND (gasp) on page under the
Chemical Weight Table FAC should read as 2g per tsp and add that a cup of
FAC is 100g. I'm sure this won't be my last mistake I have to eat crow on!
When weighing the stuff out the day before in time for class, I noticed
either the FAC I got had gotten MUCH fluffier or my measurements were off.
Luckily Don Bryant and Sam Wang corroborated with their scales that in fact,
my brand new wonderful gram scale is correct. (don't worry--this doesn't
affect any other formula in the book). That should teach me a lesson about
trying to make loosey goosey kitchen recipes with teaspoons and tablespoons,
but really, with cyanotype it works! It's not like mixing up precious
metals...
Chris
Received on Wed Feb 15 11:45:21 2006