Re: question for silver gelatin users

From: Kate M <kateb@paradise.net.nz>
Subject: RE: question for silver gelatin users
Date: Mon, 29 Nov 2004 22:38:23 +1300

Thanks for your response... It's always interesting to compare what
people do (against what I tried, currently do, and thought about).

> Sizing related:

> - how do you size? (brush, roller, dipping, etc.)
> I size by bath. Two coats, 12-24 hours drying between.

Is it better than brush application? Or is it just to save work? I
tried sizing by immersion but unless I size small pieces and hung dry,
there is no way to dry the paper without damaging it. (The sizing
solution sticks paper to whatever after drying.) I ask this because I
sometimes suspect that quality/uniformity of sizing affects uniformity
of emulsion coating rather significantly.

> Emulsion coating related:
> - how much solution do you coat (specify size)?
> Per suare metre? I don't measure....

Per square (deci)meter or 22x30 inches or 80 square inches or whatever
unit... but if you don't measure...

For my current chlorobromide enlarging emulsion, standard coating
weight is 80-100ml per sq. meter (2.5+g AgX/sqm). 100ml gives me very
nicely dense black in shadows. But this level of coating can be
achieved with two thick coats or 3+ thin coats using foam
roller. I wonder if this is what people do as well. (I used to make
emulsion thicker than typical and also used to make thicker single
coats but I didn't like the results. My current emulsion is not very
optimized but the image looks crisper, the emulsion is considerably
easier to make also taking less time to make a batch.)

> - how do you coat? (brush, roller, dipping, etc)
>
> Brush first, then roll for a smooth surface. I find that applying by
> roller I always get bubbles. Can't get a decent smooth surface roller
> here (or can't find where to get one)

Doesn't the emulsion stick to the roller? (What kind of roller is it?)

I use fine grain foam roller, but unless I maintain emulsion viscosity
rather tightly, the coated paper surface turns out mottled/speckled
and this is quite ugly. To suppress bubbles, I have to use quite a bit
of surfactant and antifoaming agent, and then immerse the roller in
the emulsion in the dish, roll back and forth a few times to soak and
squeeze out the emulsion. Then coat. Quite a bit of emulsion gets
wasted...

--
Ryuji Suzuki
"People seldom do what they believe in.  They do what is convenient,
then repent." (Bob Dylan, Brownsville Girl, 1986)