Re: humidity and gum coating (was: Re: palladium bleeding once again
Yep, that sounds exactly like my method; just shows there's nothing
new under the sun. Thanks for looking that up for me.
I did just try this with Arches bright white, and it seemed to work
fine (although for a while I didn't think it would, as the soluble
coating in the beginning of development was coming off the less-
exposed areas in a really ugly splotchy fashion). But it wasn't a
good test, really; I should have done it yesterday when the humidity
was so low and I was having difficulty getting the coating to brush
on smoothly.
Katharine.
On Sep 2, 2006, at 6:29 PM, Venkatram Iyer wrote:
To alleviate your distress, the text explains:
Soak the paper in room temperature water (I dunked it in water,
hung it till it stopped dripping). Place it on coating board,
gently blot it till no visible water reflection is visible and
apply the emulsion. You may not need to even out the coat with a
hake. Dry in semidark or force dry with hairdryer set on cool. Best
to expose after the coat dries.
Hope this works. Rajul
On 2-Sep-06, at 5:16 PM, Katharine Thayer wrote:
On Sep 2, 2006, at 4:22 PM, Venkatram Iyer wrote:
Christopher James in his book on Alternative Photographic
Processes describes the wet coating technique on p. 235. I have
tried it and it works really well. Rajul
Thanks, Rajul. I just found out something distressing, though;
when I went to dig James out of a box (I still don't have my books
unpacked) I found that I don't have any of my alternative-process-
related books with me. That box must have gone into storage by
accident, along with my statistics books.
So does he basically recommend soaking the paper and blotting it
before coating, as I did, or is his wet-coating method something
different than that? Thanks,
Katharine
On 2-Sep-06, at 8:23 AM, Katharine Thayer wrote:
Chris, this makes me wonder if anyone has ever tried humidifying
paper for gum coating, to make the coating easier in dry
climates. The reason I'm wondering this is that my humidity,
ordinarily >90%, has been way down for the last couple of days
(17% yesterday afternoon) and I was having a heck of a time
getting a smooth coat with my usual straight gum (no added
water) mix. I decided that if this keeps up (unlikely) I'll
need to start adding water to the mix, but your troubles with
palladium gave me to wonder if anyone has reported humidifying
the paper to make the coating easier. I do know that I once
coated and printed on wet paper, just to see if it could be
done, and it coated beautifully and printed fairly well, except
for a sort of mottled effect in the background. Here's the test
print I posted at the time:
http://www.pacifier.com/~kthayer/html/wetcoat.html
At any rate, that combined with your explorations around
palladium have led me to musing about whether humidifying might
give a better result.
Katharine
On Sep 1, 2006, at 10:10 PM, Christina Z. Anderson wrote:
Well,
Happy Labor Day weekend everyone! It may be a true "labor"
weekend for this
household after all, because my daughter is having her baby in
my bathtub
any day (or hour) now. Hmmm...that sounds strange....we do
have hospitals
in MT....ohhhh, never mind...
At least I got somewhere today with the bleeding issue. My
Platine shipment
came in and I was ever so excited to see if the new batch would
be different
and not bleed. Alas...it still bled like crazy.
SO, it helped that Mark Nelson said that at the Formulary (also in
MT--similar humidity) they had to do two things to get good
prints on Cot
320 this summer: humidify 30 minutes before coating and 30
minutes after.
I've watched the humidity all summer and it has hovered around
30%.
I messed around with the humidity and Everclear variables--
using Everclear
or not, humidifying before and not after coating, humidifying
after and not
before coating, humidifying both before and after. I built
myself a
makeshift humidity box with a couple of trays and stuck a gauge
in there,
too.
(Of course in the meantime throughout these tests I am racing
first to the
hardware store for screening and then to the liquor store for
my flask of
Everclear...I thought of downing the bottle on my way home.)
What I found was it was most important to humidify after
coating, more
important than Everclear or having the paper humidified
before. If I
humidified before coating, the paper tone was greyer and
duller. If I
humidified after coating, for 30 minutes (70% humidity) while
the paper was
drying, there was no bleeding. So it must be as Clay suggested--
the stuff is
drying too quickly on the paper surface and not sinking in
enough. It was
so bad on a couple of my test sheets tonight that I could
literally take my
finger, wipe the wet surface of the print, and have black
stains on my
fingertip. I was losing quite a bit of density in the print
all over,
including highlights, and even had serious staining/bleeding
into the
highlight area, too.
So tomorrow I am going to have to develop a new set of curves
with this
after-coating humidity factor, and will continue this procedure
to see if,
in fact, the bleeding completely stops. I just have to find
someone to
build me a drying/humidity rack, now....
I'm still puzzled, though, why during the last couple years I
never
experienced this, and now I do. If someone has a friend at
Arches, could
you ask if their paper sizing has changed in the last year?
BTW, that green ink on the Epson 2400 is sure as heck dense.
The end.
Chris
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