Re: Overexposeure was Re:Pinhole gums
Hi Katharine, Marek
Yes-- as much as I love spending time on an uncrowded island, the
big downside is being at the mercy of the ferry schedule.
Thanks for taking the time to try to figure out my gum printing
problem. I am saying that all the prints that gave me trouble were
printed in the same kind of weather-- sized outside in unusually cold
and dry weather and printed inside in unusually (for inside) cold
temperature.
None of the prints would develop by simply soaking for hours in
water, or even when running water over the prints. A few (though not
all) "developed" to an extent by fairly vigorous brushing, which
still left some of the print undeveloped and the rest of the print
just okay-- always with staining in the highlights-- but I could at
least see the image.. A few wouldn't develop at all, even with
brushing. All of those prints were done on the paper I'd sized
outside in the cold dry air.
And you're right-- I did make a perfect score on the color test --
well, once I got upstairs to my calibrated desktop screen. :) But
although I did notice everything drying quickly, I was pretty fast
with the brushing-- and I was keeping the gelatin warm-- so I didn't
actually have any noticeable trouble when brushing it on the paper.
If it's warmer tomorrow, I'm going to try printing with the same
sized batch of paper, maybe in a warmer part of the house, and see if
that makes a difference.
I mentioned that I could see a faint outline of an image, after
exposure, only to say I hadn't made the mistake of coating on a too-
thick layer of gum/pigment/dichromate or anything.
I don't know. Again, the only real difference that I can come up
with was the cold weather. ??
I just saw your post, Marek, and that's a thought about too much
hardener. Again, I add the hardener to the warmed gelatin and
thought I added the amount I normally do, but it's possible I made a
mistake...
Anyway, thanks again. I'll try what you suggested and keep you
posted.
Diana
On Nov 30, 2008, at 11:04 PM, Katharine Thayer wrote:
Hi Diana, glad you made it home. I lived on an island during one
of my former "lives" (a very happy one it was) and I know how life
runs by the ferry schedule on an island.
Okay, I'm still not sure, so you're saying that all the prints that
you had trouble with on that paper were printed in the same kind of
weather, unusually cold and dry, or not? (Actually, I'm not sure
it matters all that much, since you weren't printing outdoors, but
in your humidified workspace, but just trying to cover all the bases.)
The other answer is disappointing :--) because I was hoping to rule
something out, but if sometimes you could get a fully developed
image by brushing and sometimes you couldn't, then it really makes
no sense. We're fond of saying that almost anything that can be
said about gum can be contradicted, but when we say that, all we
mean is that gum is so versatile and flexible that the results are
affected by many different variables and the interactions between
them, and so different people working under different conditions
and with different equipment/materials will have different
observations about the particulars of how gum works. But while
that's true, that the particulars of gum can vary from one
practitioner to another, at the same time gum does behave lawfully
under a particular set of conditions/protocol and should perform
in a repeatable fashion within one printer's practice, everything
being held reasonably constant.
If you could always develop an image by either long still-
development or by brushing, then the logical conclusion would be
that the problem is gross overexposure (then the next problem would
be trying to understand the cause of the overexposure). If you
could never obtain a fully-developed image by either long still-
development or brushing, then the logical conclusion would be that
the problem is either stain or (much less likely IME) an overall
hardening of the gum layer, as Mark suggests. But if it's
sometimes one and sometimes the other, then it's impossible to draw
even tentative conclusions without more information. The only
possible, though somewhat unlikely, explanation I can think of for
this inconsistency might be that the weather varied during the
period of time you were having difficulty printing on that paper,
and under different weather conditions the overexposure was
sometimes not as profound as at other times, making it possible to
brush-develop the image during those times.
That said, I have to say that in all my years of printing gum, I
have only twice seen gum so profoundly overexposed that the image
could not be developed by long development or by brush-
development. Once was when someone came to the door when I was
exposing a print, and I left the print to answer the door and then
forgot about it in attending to the business of the visitor, and
the print exposed until the light burned out, a couple of hours at
least. The other time was when I put a print frame on a black
tarpaper roof on a hot sunny day and exposed in direct sun for five
minutes. In both cases, I suspect it was more a thermal hardening
issue than straight overexposure per se: the gum layer was
hardened throughout by the heat that was generated in the print.
But those were both very extreme cases, and I'm not inclined to
believe that overexposure this extreme could be caused by the
conditions described here.
However, the explanation you seem to be satisfied with, that the
gelatin "dried too quickly" makes no sense either.
It seems the word "drying" has been used in a confusing way in this
discussion, which has served to conflate two different issues.
You have two things going on: the gelatin setting up, and the
paper/gelatin drying. As the gelatin cools it becomes more solid
than liquid, but that's not the same thing as the gelatin drying on
the paper, which has to do with moisture content not temperature.
Generally it doesn't matter how fast the gelatin dries once it's in
the paper; the faster the better IME, because I don't like waiting
all day for it. The garage where I hang my sized paper is "solar
heated" by virtue of the fact it has no insulation and a metal
roof, and on a sunny day the sized paper is often dry almost as
soon as I hang it up. The quickness of the drying has no effect on
the effectiveness of the size. The possible explanation offered,
"the sizing dried too quickly, so it was as if the paper had no
sizing at all" doesn't seem to me to be anchored in observable
sizing reality. And if you mean the gelatin set up too quickly,
then it makes even less sense, because when the gelatin sets up too
quickly, you have a problem of too MUCH sizing, rather than not
enough sizing.
That would be the most likely consequence of sizing outdoors on a
cold dry day, as David and Chris suggested: the gelatin would set
up so fast that it would spread on thick and viscous and sit on top
of the paper rather than soaking in as a liquid, like it should.
While this is a likely result of sizing outside in cold weather,
I'm skeptical that this is the explanation for what we're dealing
with here, for two reasons: (1) Diana says she didn't notice the
gelatin setting up, and I would think you'd have to be awfully
unobservant not to notice that. Since she scored a perfect score
on the color discrimination test, I'm not inclined to describe her
as unobservant. (2) the problems that getting the gelatin too
thick and viscous would introduce in printing/development are
different from the problems Diana describes. Yes, it might make
the brush drag when coating, but the too-thick sizing would
prevent any pigment staining problems, so staining wouldn't be an
issue, and the too-thick sizing would be unlikely to be related to
overexposure as well. What a proper sizing does is sink into the
paper and leave the tooth open for the gum to cling to. A too-
thick sizing, which is what you'd get if you brushed the sizing on
too cool when it's already setting up, will clog up the tooth so
the gum doesn't have anything to hang onto. So what happens when
you're printing gum on a too-thick size layer like that, is that
the gum won't adhere to the support and will flake off or slough
off in development. That's obviously not what's happening here, so
I don't think the gelatin cooling and setting up too fast is
responsible for the problems Diana describes.
I did offer a kind of off-the-wall hypothesis about the gelatin
evaporating off the paper in the cold dry wind. I have no idea if
that's even possible, but if it were, at least it has the advantage
of offering an explanation for Diana's problems, if it turns out
that the problem is stain rather than overexposure. But it's a
REEALLL long shot.
I'm inclined to think that the whole sizing thing may be a red
herring, that the printing problems may be unrelated to the fact
that the paper was sized on a cold dry day, but that's just
conjecture on my part. Occam's Razor points that way, I think,
because the only way to connect the sizing to it it is to come up
with a new unsubstantiated theory, and I find things usually have a
more accessible, sensible, logical, and evidence-based
explanation when it comes right down to it.
I was working on a way of organizing variables to try to make sense
of this, but had abandoned it while waiting for answers, hoping to
rule out some variables at the outset. Now I'm tired and have
rather lost heart for the enterprise; there are altogether too many
unknowns in this equation.
Oh, one more thing, Diana: you seemed to be putting some stock in
the fact that you were getting a faint printed out image after
exposure. IME, that means nothing. Sometimes you get a faint one,
sometimes a strong one, sometimes no printed out image at all; in
my experience there is no connection between the presence or
absence of a printed out image, or of how detailed it is, and the
quality/tonality of the image that eventually emerges from
development.
Good night all, hope any of this is useful to anyone,
Katharine
On Nov 30, 2008, at 4:29 PM, Diana Bloomfield wrote:
Hi Katharine,
Finally found the cat, and we just got home. Whew. It's been
pouring rain here for 2 days. Anyway, I sized this particular
batch of paper (maybe 25 sheets, both Rives and Fabriano) outside
in dry colder than normal weather. Then, over the next few days,
I tried printing on both kinds of paper-- I had trouble with every
one I tried, though I still have some left. I gave up after a
while, thinking it might be my darkroom space which is colder than
the rest of the house, but the temperature in there was probably
about 60 degrees.
I would leave the print in water for hours-- picking it up,
nothing had changed from the time I took it out of the vacuum
frame. I ran water across it-- still nothing. I then brushed it
fairly hard, and that helped-- you could see an image, though
there was staining in all the light areas. I only tried one coat
on these, because I just didn't like the way it looked-- but on
several of them, I did get a fully developed image-- only after
brushing continuously. So it sounds like overexposure and
looked like something that just hadn't been sized at all (to me).
On Nov 30, 2008, at 2:44 PM, Katharine Thayer wrote:
Diana, I keep thinking you're gone, but if you're still there,
two quick questions:
(1) I'm confused about the conditions under which you're having
these printing problems. Was it only when the weather was cold
and dry, or is it any time you use the paper that was sized when
it was cold and dry, regardless of present conditions?
(2) You said that brushing "helped" but that the image
essentially didn't develop; I don't understand that. Are you
saying that even with brushing, the image didn't fully develop,
or that brushing after a long soaking that didn't develop an
image would eventually result in a fully developed image?
On Nov 30, 2008, at 11:23 AM, Diana Bloomfield wrote:
Hey Mark,
That's a thought. As advised by the woman at Photographers
Formulary, I keep the bottled glut in the refrigerator, so when
I get ready to use it, I take it out and have never even
bothered to warm it up-- I just add the required amount in the
warmed up gelatin. But I guess that could have happened. I did
have the gelatin in one of those electric glue pots that keep
everything at a constant 140 degrees, so it stayed warm-- until
I was coating, but I was very quick about it-- I think maybe it
just dried too quickly. I also used different types of paper
when sizing, both Fabriano and Rives BFK, and got the same
results from both. The only difference in what I normally do
was the (relative) excessive dry cold.
On Nov 30, 2008, at 2:16 PM, ender100 wrote:
Could it be that the hardening agent you are using for the
gelatin did not activate in the cold well and then when you
coated with the gum, it was causing a hardening of the gum?
I would try sizing a sheet in "normal" temperature and
humidity and then try a gum print on it and see what happens.
Fall seems to be when lots of people have problems with
printing due to changes in temperature and humidity.
Best Wishes,
Mark Nelson
Precision Digital Negatives
PDN Print Forum @ Yahoo! Groups
Mark Nelson Photography
On Nov 30, 2008, at 1:11:45 PM, "Diana Bloomfield"
<dhbloomfield@bellsouth.net> wrote:
From:"Diana Bloomfield" <dhbloomfield@bellsouth.net>
Subject:Re: Overexposeure was Re:Pinhole gums
Date:November 30, 2008 1:11:45 PM CST
To:alt-photo-process-l@usask.ca
Hey Katharine, David- Still here-- we were on our way out the
door to catch a ferry to get back home, and then our cat
managed to hide herself so we couldn't leave. We finally found
her hiding in a closet-- anyway-- as far as overexposure-- that
is what it sounds like, though I was using the same exposure
times as before. So-- since this was without the usual
humidity, it couldn't have been overexposure, right? On Nov 30,
2008, at 2:05 PM, Katharine Thayer wrote: > > On Nov 30, 2008,
at 10:51 AM, davidhatton@totalise.co.uk wrote: > >> That's
right Katherine. Higher humidity faster printing..What was >> I
thinking?? >> >> It just looks that there is some kind of over-
exposure thing going >> on here.., hmmm > > Yeah, I know, it's
confusing, and I agree that it looks like > overexposure, that
or possibly (but less likely IMO) pigment > stain. I'm trying
to work up a flow chart kind of thing that > would help us
organize what variables and elements we're looking > at,
because reading back through the thread I found the discussion
> very confusing. Stay tuned... > kt
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