I have had many a nest of mold on my cyanotype "A" solution. I just grab
it with a pencil or pen and throw it away. The stuff seems to cling
together in one big disgusting globule. I suppose if you were worried
about excess mold being left behind you could filter it. I have never
bothered and am currently using the same "A" solution for the past year
and a half without any ill effects to my prints. It is interesting to
note that you get mold growth within a few days, it usually takes me
several weeks.
In regards to the "B" solution I don't think I have ever thrown any out,
just used it up. I have had the same stuff sitting around for a year or
so.
According to Mike Ware, prussian blue, which is what a cyanotype is made
of, is soluble in water. At worst you may need to use hot water. Bleach
should not be necessary.
> Question #2: Solution separating: I have this habit, and I'm not sure were
> I picked it up. I'm convinced that the "A" and "B" solutions, once mixed
> together, will separate out. I thus pour the mixture back and forth
> between two beakers a few times before each paper is coated. I have no
> memory of were I picked this up, am I wasting my time?
>
> And for those who want to know: Yes, "Cyanotype Neurosis" is a mental
> illness recognized by the American Head Shrinkers Association. In two
> states (California and New York) it is even a viable legal defense ;-)
>
> tomf2468@pipeline.com (Tom Ferguson)
I don't think it can hurt to thoroughly mix your solutions. Why not pour
them back and forth. I usually just swish them around in the graduate I
am using. I have on more than one occasion quit in the middle of a
blueprinting session and left a container with some senstizing solution
to sit overnight. I have observed that the soultion usually turns blue
long before it will fully drys out. When it does dry out you will be
left with a dark "prussian" blue layer lining your container. I think
the chemical reaction that we use when we expose blueprints continues to
happen with or without light. My point is that there is no chance of the
2 soultions separating out. They will instead change to their final
form. Even this will certainly not happen so quickly for you to have to
worry about it.
However, if the mold is still getting you down, you should try Ware's
cyanotype formula. Better blues(with one coat anyway) faster printing
speed and not as seemingly necessary to double-coat for a good dmax.
There is a link to his website on the alphotoFAQ where you can find his
paper on his new process along with other goodies. B&S and the Formulary
sell the senstizer. WHile considerably more expensive than the "classic"
formula, we are still talking pocketchange per print.
Salvatore Mancini