Re: Tiny Bubbles In The ... Gum

Michael,
Yea! Another gum printer!!
I use about 2.5 ml or 1/2 tsp for an 8x10.
This brings up an interesting point, the bubble thing. I think you mean
fisheyes, where the gum separates into open spots. I find this happens most
often with my magentas, and was wondering if some pigments were "oilier"
than others...I used to think it was that the magenta was the last coat and
therefore the surface was slicker and that's why it happened, but yesterday
when I had the pleasure of teaching Mark Nelson a thing or two for once
(heheheh--he was passing through Bozeman on his way from his PDN Formulary
workshop and we did gum all day), it happened with a first coat of magenta.

I usually have related fisheyes to loss of viscosity for whatever reason,
whether the gum is too thin (my usual reason) or the surface getting too
slick from too many coats, but it seems to happen more often with certain
pigments.

I can dig up my list of fisheye reasons from my notes but it'll take a
while, as I am still unpacking and will be for a month.

I do use a hake, like Dave, and I love mine as it is old and seasoned and
never sheds and is soft. I brush like Dave does, too, one way and then
another and then one way again and then let it sit and sink in. Then, if
needs be, I go over it with a Badger Hair brush ($under $20 at Jerry's
Artarama). I noticed my favorite hake brush is a connoisseur brand.

Never double coat without exposing in between (you can coat, expose, coat
again, expose and THEN develop, which is Philippe Berger's method, but you
have to be very careful not to get grainy and flakey with that process).
Your "dmax" issues in gum relate to pigment load and exposure to create more
depth of layer and a deeper color, so it is not like platinum or whatever.
Chris

From: "Michael Koch-Schulte" <mkochsch@shaw.ca>
. I was getting quite a bit of
> bubbling in the emulsion as I brushed it on, my coating settled down a bit
> but the unevenness was apparent to me afterword. Is there something I can
> do
> or add to my emulsion to counteract this? Is it my brushing technique? My
> brush? I

 Also, for a
> "one-coat" print, generally, how much emulsion should I be using for an
> 8X10
> print?

Do people double coat gum?
Received on Mon Aug 29 08:27:38 2005