From: Eric Neilsen (e.neilsen@worldnet.att.net)
Date: 05/02/00-07:21:06 PM Z
Judy Seigel wrote:
> On Tue, 2 May 2000, Eric Neilsen wrote:
> > ...the Ware/Malde process does not REQUIRE the dry and rehumidify. It
> > does show how the humidity will affect color and speed of the print. Ware
> > also provides, through that paper, specific color that can be achieved by
> > specific humidities.
> >
> > I think that we can all agree that the eye can judge whether a print has a
> > desired look. If one can get that color by simply drying a coating with
> > cool air and quickly printing, or by drying and rehumidify, each method can
> > work well. I see an advantage in slowly adding humidity, 30 minutes or so.
> > In that, one should be able to achieve a more even humidity level throughout
> > the paper. I have seen this as one fall back in Zia type print from reports
> > on this list.
>
> But a propos of hair dryer drying and SAFETY -- I've read one shouldn't
> hair dryer pt-pd because chunks of metal could flake off and float into
> your respiratory tract... Seemed far fetched to me, but it's said.
>
Particles of platinum are, as I understand it, able to produce a form of asthma.
I use a particle mask and eye protection when working about 11x14 and on those
rare occasions that I use a hair dryer.
>
> Also, apropos of the ferric oxalate tests -- some years ago when i had a
> short spell of kallitype & pt-pd, I used the k ferricyanide test on my B&S
> ferric oxalate. It turned blue, & I discarded it (directly into Farmer
> Brown's well) and ordered some more. I mentioned this to Melody on the
> telephone & she told me "that potassium ferricyanide test doesn't work
> with the Bostick & Sullivan ferric oxalate." Which is to say, it was
> apparently still good.
>
> Judy
I seem to remember that Richard brought this up several years back when I was
questioning him about his ferric in the alt group. He was talking about using the
silver nitrate test. This is good if you plan to use the ferric for kallitypes,
but not needed for platinum/palladium use of ferric oxalate. I will wait for
Carl's chem friends to comment on the blue not holding true for B&S ferric.
Perhaps, Vicente or Jeffrey might know. Perhaps, something else in B&S was the
problem. Who knows, haven't used the stuff in 5 years.
-- Eric J. Neilsen 4101 Commerce Street, Suite #9 Dallas, TX 75226 214-827-8301 http://e.neilsen.home.att.net http://www.ericneilsenphotography.com
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