Re: Clearing cyanotypes, minimizing bleeding into highlights
> Cyanotype is very paper sensitive. Is the Crane's Diploma Parchment
> the same as Cranes Weston? If so, it's one of the more fool proof
> papers to use.
I hate not being complete in an e-mail:-) Yes, full name seems to
Crane's Weston Diploma Parchment
(which is very nicely described here
> For exposure, I would cover a part of the coating with a piece of
> opaque paper, to insure it receives no exposure. That part would
> should be perfectly clear of blue after 'development'.
I will do that tonight.
> Adding a little acid to the water is a good idea. However, in your
> case I would try skipping the acid and see if your water needed it,
> and to see if that's the cause for your staining.
I will try that too - and get a Ph checker in the meantime.
> Yes, Mark was correct. I leave the print float up-side-down for 5 to
> 10 minutes. Then I would give it a gently rinse and hang up to dry.
So you float - no water change - just in a tray - say nearly
full with water.
Do you then lift paper out, dump (blue) water, and wash in
clear water tray?
> But running water over the print the whole time wouldn't be a
> problem, except in some cases it could get rid of some highlight
I'm worried the running water is "smearing" the Prussian Blue?
Do you brush coat or rod coat?
> With the right paper, the whole process is very simple and quick. You
> definitely don't need to watch movies in order to wait for it to dry!
I still like to watch movies though!
> Good luck.
> Sam Wang
> On Jan 4, 2008, at 9:14 PM, Brian Pawlowski wrote:
> > Hi. My first post - and its a basic one. I've been wading through the
> > archives and searching and reading all my references and I'm somewhat
> > frustrated.
> > The only thing holding me back from doing cyanotypes is the
> > difficulties in clearing the print without blue bleeding into the
> > highlights. I cannot maintain paper white. I've been using the PDN
> > system to calibrate my exposures (been playing with Pd, POP, Silver -
> > cyanotypes keep driving me back to Pd printing). Mark Nelson made some
> > suggestions and I combined with some reading and interpolation and am
> > doing:
> > - Traditional Cyanotype (Bostick and Sullivan kit).
> > 3:2 mix (A:B) - to increase speed. Two drops Tween 20
> > per 10ml emulsion.
> > - Humidity is 50-60% in room - paper left out for at least
> > 1/2 hour to stabilize.
> > - Brush coat (hake brush), work emulsion to paper to get a
> > consistent layer with fairly gentle strokes
> > - Air dry about 2 hours (I know, I know - Mark keeps telling
> > me to be consistent - I watch a movie during drying).
> > - Been focusing on Crane's Diploma Parchment from B&S -
> > calibrate to a 2m 56s exposure using 31 step tablet and X-rite
> > 810 (I think) densitometer. (Diploma Parchment has
> > much better wet strength than Crane's Platinotype
> > had it seems to me)
> > - Dmax 1.29+ (partly because I am not using hydrogen peroxide
> > any more as I think it aggravated the bleeding into
> > the highlight areas). And 21 steps of scale.
> > - Mark passed on Sam Wang's (?) suggestion to clear the exposed
> > paper inverted in a water bath. I add about 5 ml of a 1:100
> > dilution of Hydrochloric Acid to about 2 liters of clearing
> > bath to start.
> > - I run water into the bath slowly to allow the water to change out
> > the blue and keep it up until it remains clear (about
> > 1/2 hour). No hot water - so tap water circulating is about
> > 50 deg F at this point? (don't have the Ph of my water -
> > sorry).
> > - Remove print, lay on paper towel - lay another sheet of paper
> > towel on top - remove excess water, dry flat face up.
> > I'm wondering if I am asking too much from the process?
> > Any words of advice?
> > Mark suggested someone had success with Arches Platine - which
> > I had some of and I gave it a whirl - the paper is slower with
> > the same steps above - by 1 stop or more?
> > HELP!
> > Thanks:-) And Happy New Year!
> > Brian