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Jacek,
Where's the Stouffer stepwedge you shot with these
test prints? You do own a Stouffer wedge r-i-i-i-ight? ^) Until you shoot that
you have no idea if you're getting the correct dMax in the print. I routinely
shoot my gums at 14 minutes for many, but not all colours. The time used is
based on how they test with the wedge. Also, if you're calibrating your
negatives using an imagesetter you might want to consider making a
stock pigment/gum mix at this point and then adding equal amounts of potassium
dichromate, gum and water to that.
~m
----- Original Message -----
Sent: Thursday, April 26, 2007 12:24
AM
Subject: Unknown area in Gum
printing?
Hi all,
I tried my second attempt. Just a basic outline
first on what I did.
Arches smooth 300gsm and Fabriano Acquarello
300gsm
1. boiling water pre shrinked for 10mins. Dried for a day.( no
more speckles in the Arches)
2.Gelatin 3g to 500ml, cold water for 10
mins... Heated to 43 degree Celsius.
3.Added paper to the tray of gelatin
for a minute, took excess gelatin off by sliding the paper on the side of the
tray. Dried for the day. Stored the same Gelatin in the fridge
4.Reheated
the gelatin the next day. Recoated the paper the same way. Dried.
Didnt
add any hardner as yet, as I cant seem to get time to go buy any!
:)
5ml 13% Pot Dich + 5ml Gum 35% + Windsor&Newton LAMP BLACK a
very SMALL smudge! (coudnt get any Ivory black as yet, will do
so..)
Coated paper, fan dried for 15mins.
Added a negative with
squares 2% increments made in photoshop from white to black. Each 2% square
has a number on it, which should clearly be seen when printed.
The
sheet of Arches had 3 of the same negatives on it, each exposed 4, 6, and 8
mins. Just covered each negative when it passed the min mark.
Developed
for 5 mins face down in room temp water.
Next tray developed for 5 mins
face down in room temp water.
Next tray developed for 20mins same room
temp water.
On the Arches paper I got:
What I got was NO staining in
highlights or midtones or the whole paper. They looked ok though a little on
the light side the tones came up.
Can read all the incremented 2% numbers
in those areas.
The shadows are another business altogether, what I got
was a massive yellow staining probably from the dichromate, plus it looked
like a real mess as I couldnt really make out the incremental numbers from the
negative. The mess seemed like too much watercolour overpigmented, its not one
colour but just smudges of watercolour and yellow staining.
Reading
Katharine suggestions, I'm thinking what I'm looking at could be OVERexposure?
or the small Smudge I used from the lamp black is still too much
pigment!?
I doubt it was caused by overcoating, as I turned each of the 3
negs upside down side by side, got the same result on each part of the
print.
Could it be my sizing, and not using a hardner? Though the
Highlights and Midtones look good?
I got kind of fed up looking at the
yellow staining and used a 5% potassium metabisulfite solution, sprayed with a
hand held spray gun. Didnt work as well, next time i'll use a tray
bath.
The other Fabriano Aquarello paper I'll add more info on it later
can't recall what it looked like, but had the same sort of problems as
above.
I'll scan the prints when I get home and upload to a
website.
Cheers
Jacek
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