It can't POSSIBLY be this...
I mentioned a while back problems with runoff with Cyanotype. I've
tried a few papers over a long time - and was finally trying Crane's
Weston Diploma Parchment.
I kept getting a lot of run off and bleeding into highlights. I did
get a PH meter after someone commented on Bay Area water (mine reads
about 8.3) - so I consistently acidify (very very dilute hydrochloric
acid - pool chemistry - cheap). I follow Sam Wang's advice through Mark
Nelson to clear inverted. I am using Classic Cyanotype - went from 1:1
Solution A to Solution B to 3:2 - but then as my highlight bleeding
problems plagued me I went back 1:1 (and with a new UV box my exposures
are 1m 50s even at 1:1).
But Judy Seigel sent me a note along the lines of "This is a really
simple process. Why are you using a hake brush - use a foam brush.
I went to Home Depot, and picked up a couple cheap black foam
brushes with wooden handles. After several back and forth
tests, I'm concluding the foam brush outperforms the hake and
Richeson brushes for my cyanotypes - I'm getting virtually *no*
runoff - whereas before it looked like a Smurf took a bath in
Can it *really* be that simple? The foam brush moves more roughly
across the paper surface. Kevin Sullivan in an e-mail sometime back
when I made a comment about runoff on COT 320 said it might be
necessary to rough up the surface (to break the sizing?) on very smooth
papers like COT 320.
Anybody want to weigh in on this? I've been mostly running calibration
sheets (step tablets for PDN work). I'll probably do a few prints
My only concern is that the foam brush will abrade the surface of the
paper too much with resulting loss of image detail (on the other hand -
cyanotype running off willy nilly and bleeding into highlights suck).