Re: Gum woes

Hi Joe,

It might be and i'll have to test that also; once I get done ripping up 50
sheets of Fabriano Uno and Arches Aquarelle tonight. I don't know why I was
doing that; I guess I was letting the paper set because that's what I do
with other processes (cyanotype, kallitype, ect...). The combination of
different paper, a 1+10 or 1+20 gum to pigment ratio, and a 1+1 gum/pigment
to dichromate ratio will probably make a world of difference. It was
probably just my luck to choose all the wrong variables, but to learn it is
to live it. :>)

Regards, Scott

swphoto@verizon.net

----- Original Message -----
From: "Joe Smigiel" <jsmigiel@kvcc.edu>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Sunday, May 08, 2005 10:38 PM
Subject: Re: Gum woes

> Scott,
>
> When I mix an emulsion (either using tubes or powders) a large part of
> it is by feel acquired through experience. I vary the amount of
> pigmented gum in the mix and generally use between a 2:1 and 1:1 gum +
> pigment to saturated dichromate solution ratio, depending on what I'm
> trying to achieve with the coat.
>
> For me, the viscosity is correct when I can coat an 8x10 or 11x14 area
> in one direction and then even it out at 90 degrees immediately. If the
> mix (and humidity) is right, the emulsion starts to set once this is
> accomplished. I follow this with a smoothing with a dry fan brush first
> in one direction and then the other, again immediately. The emulsion
> has set in this time which is probably on the order of 45 seconds total.
> I then dry it in the dark for several minutes using a hair dryer
> without heat. I've never let the emulsion just sit there on the paper
> for a minute before smoothing. Perhaps this is contributing to your
> problem.
>
> Joe
>
>
> >>> swphoto@verizon.net 05/08/05 9:41 PM >>>
> Hi Kate,
>
> I hadn't thought about having too much emulsion. To me the second and
> third
> coats seemed thin but then again i'm just a beginner with gum - most of
> my
> work is with silver gelatin, cyanotype, kallitype, van dyke, salt, and
> albumen. Basically I use a 1-1/2" hake to spread enough emulsion to
> cover an
> area a little bigger than the image without puddling, let it sit a
> minute,
> then use a dry 4" hake to smooth out the coat. I have a couple of foam
> rollers here somewhere I can dig out, so i'll have to try your
> suggestion
> this week.
>
> Regards, Scott
>
> swphoto@verizon.net
>
>
>
> ----- Original Message -----
> From: "Kate M" <kateb@paradise.net.nz>
> To: <alt-photo-process-l@sask.usask.ca>
> Sent: Sunday, May 08, 2005 7:06 PM
> Subject: RE: Gum woes
>
>
> > Hi Scott, I'm also wondering if too much emulsion might be a problem
> for
> > you. I brush the emulsion on, then roll over it in several directions
> > with a cheap foam roller (you have to roll any excess off the roller
> > onto paper towels or similar). This makes the emulsion layer very very
> > thin ( important for gum).It also eliminates fisheyes. I find that if
> I
> > have too thick an emulsion, I have problems with graininess as some of
> > the gum doesn't get exposed throught to the paper base and therefore
> > falls off during development.
> > Kate
>
>
>
>
Received on Mon May 9 16:14:13 2005