Hallo, I just subscribed to the list, although I don't feel completely
"new" to it since I downloaded a lot of the archives, the FAQ, and I
"know" some people on the list.
I would like to tell you about my first cyanotyping experiences and ask a
few questions:
NEGATIVE
I start to make a big (20*40 cm) neg in a selfmade circular (a big coffee
tin) camera obscura on Konica Xray A2 film (any others busy with this?,
I found some very useful info in the archives), process in D19.
Start to get some reasonable negs.
PAPER
As paper I use Schleiger &Schuell GB002 blotting paper, you may have
guessed by now that I work in a laboratory ;-). This paper is also used
for chromatografy (is this paper buffered?), so strong enough for washing,
albeit fragile when wet (aquarel paper also?), and I like the texture.
COATING & EXPOSURE
I used an "own" method of coating (the paper is non-sized, as far as I can
tell), a bit hard to discribe, easy to do, which gives me a even coat
(yellow/green). I expose on a flat UV transilluminator (than the neg, the
paper, a glassplate and a weight to press the somewhat "curved" (This is
normal?)paper. Exposure time is worring me a bit "it's from 15 to 30
minutes, and that with a direct UV source. The paper gets a bit hot (30
deg celcius?), is this bad?
One of the things is that the Xray film has a strong blue base, and
probably blocking UV, (that's what I see on the exposed paper where no neg
is, a strong blue color). Also the wavelength of the UV source is 312 nm,
anybody knows what is the best UV wavelength for cyanotyping? (I have also
excess to 260 nm UV source, but that one is smaller).
RESULTS
The first tests washed away immediatly. That is they looked nice after
about 6 min exposure,but they washed away completly. So I exposed much
longer, and obtained the first nice prints. I also tried to recoat again
(How long can you store in the dark, already coated paper?), but that
didn't made a difference, the result was ectually worse.
Also did some tests on drying the paper. We have this "drying cabinet", a
closet with a about 40 deg blower, seems no difference between air dried
and cabinet dried.
This became quite a long post, I hope you are still with me, and have a
few answers or sugesstion to all me questions.
Looking forward to hear from you, and pick up new things about alternative
processes,
Groet,
Cor Breukel
http://ruly70.medfac.leidenuniv.nl/~cor/cor.html
"The Infrared Gallery"
http://ruly70.medfac.leidenuniv.nl/~cor/cor.html