Does anyone get the idea that I'm not getting much work this last month???
Good grief, no one is ordering prints, none of my commercial accounts are
calling. I am SLOW (and may soon be hungry).
Anyway.... I ordered 25ml of this stuff from Bostick and Sullivan, I
thought that it was a complicated enough "manufacturing" process that I
would let someone else do it the first time. Perhaps this will explain
some of the differances I saw? It didn't seem to get too good a review on
this list.
I love this stuff. It is faster (about 6 minutes as opposed to 11 minutes
under my light source), but more importantly it allows a contrastier
negative (exacty matches my target platinum negative...I call that
convienient. DR is 4-2/3 stops, or 0.4 to 1.8) and it has a better D-Max.
I have no way to measure reflected densities, but if I line up the darkest
step (from a step wedge) of the "old" formula with a matching tone on the
steps of the "new" type, the "new" type has two 0.1 density steps more
D-Max (my wedge is in 0.1 units, not the more common 0.15).
The 2 percent Citric Acid bath before washing is NEEDED in order to clear
my prints (seems to be optional in a lot of the liturature). The "old"
formula I used was the one in "The New Photography" which includes the
oxalic acid and dichromeate. My paper was Cranes Parhmont Wove. Give the
pre-made version a try before you write this stuff off.
P.S. I'm not spending all of my time testing. Just pulled two brand new
platinum prints out the wash, they make my heart sing. Thats what I do all
of this for, God they look great!
tomf2468@pipeline.com
>Hello blueprinters.
>I have now had a chance to let Dr. Ware's "new" cyanotype formula age
>several days. I also picked up some citric acid and prepared the required
>40% solution which I added to the sensitizer before coating.
>
>I must say that with the citric acid added, the prints do clear better, but
>it took a 20 minute, running water wash. I tried hypo clear again and was
>able to clear the whites faster.
>
>Again this time I noticed no increase in Dmax over my old formula.
>
<SNIP>
>Bob Schramm