I think I would tend to agree that inking hand coated paper is
easier than inking a regular Bromoil. At least I was very surprised
by how easily my first try inked up. I would guess that this
is because the handcoated papers are not supercoated.
Interestingly enough though, I find that my limited experience
with handcoating seems to indicate that a contrastier negative
is easier to work with. My emulsion coating technique has changed
with every print I have made and I was having a lot of trouble
with my latest print (too many variables changing here?), but
when I used a negative that previously gave good results, I also
got good results using my new emulsion. The good negative appeared
to be more open and had a higher contrast than my latest enlarged
negative which was rather soft and low contrast.
I have also been adjusting my dichromate concentration (I
have been using 3% and 5% solutions) and found that the 5% gave
better results. Maybe it's a matter of adjusting my exposures?
I think one of the problems in my work at the moment is that
I have not yet been able to nail down a lot of the many
variables involved.
I have started out with a paper soak at approx. 120 F and
then squeegee it onto a sheet of heavy glass that has been warmed
by a hot plate which has been adjusted to approx. 100 -110 F.
I find that 10ml of gelatin solution for each 35 sq. in. of paper
gives good coverage. I measure it out into a small plastic dispensing
cup kept warm in a water bath before I smooth the paper onto
the glass. Then I pour the gelatin into the center of the paper
and smooth the solution from the center out with a small comb.
I have not found air bubbles to be much of an issue in my experience
so far.
My gelatin formulation however is somewhat different. I have
not yet tried
to use starch in my mixture although I have bought a box of potato
starch to
use for just that purpose. Maybe I will try it when I next coat
paper. I have not tried adding sugar to the gelatin as I have
visions of little critters devouring my image and have been rather
hesitant to use it. Instead I have used a small amount of glycerin
in my solution. It seems to not only help with water absorption
but also allows the paper to dry with less of a curl. I also
add a small amount of wetting agent like Kodak Photo-Flo to the
gelatin solution and this seems to help minimize the formation
of bubbles.
To harden the gelatin, I use a Glyoxal bath after the paper
has been coated
and dried. I generally mix up more gelatin than I need at any
particular time and store it in the refrigerator. Adding a hardener
to the solution when I make it would not allow me to do that.
I have not worked with the process long enough to be able to
judge the relative merits of either method yet but it seems to
work well for me and I appear to get good water absorption and
a nice relief in the gelatin after soaking the matrix.
I generally use a sensitizing solution of 5% Potassium Dichromate
with an
immersion time of approx. 3 minutes for my oil paper. I have
been dipping my
paper into the sensitizer as I have been concerned that brushing
it on would
not allow for an even coating resulting in variable sensitivity
across the paper. I have also wondered whether the gelatin would
be completely sensitized or if it would just be a surface effect.
When I think about it, brushing would probably be preferable
if it works well, because of the lower amount of dichromate that
would be washed out during clearing.
To clear the print after exposure I have been using Potassium
Metabisulfite.
Simply because I already use it to clear my gum prints and I
have it on
hand. It seems to work well but I have found that if I leave
a print in the
solution a bit too long the more heavily exposed areas of the
print begin to
take on a blue tint.
That's pretty much the process I am using at the moment but
that could
change at any time. So far this method has given me the best
coatings of any
technique I have tried so far and I will need to play with it
for a bit just
to see how well it works for inking.
On Exposure
As of yet I have not done any rigorous exposure testing because
my papers
have been so variable up to now. My method has been to tape the
negative to
the paper (no split back print frame here) with '3M Paper First
Aid Tape".
Just stick the tape in the margin of one side of the sheet of
film so it acts as a hinge. It is relatively transparent to UV
and is fairly low-tack. I will check the paper by lifting the
film after my first exposure and if the dichromate has not darkened
yet in the highlight areas of the print, I will expose for a
longer time.
The darkening of the dichromate is quite apparent and I am
able to see the entire image on the paper after exposing. The
stain comes out after clearing and a fairly obvious relief can
be visible. When I use my known good negative I can ink the paper
quite easily.
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