Re: Indigo

You could also add a little quinacridone red as real indigo has a touch of
red. How much of it is up to your liking. The color of real indigo ranges
from purple to violet. In an acidic environment, the flowers are redder, and
in a more alkaline environment, the flowers are bluer. I believe this is the
same principle used in lithmus paper also.

Of course most "indigo" colors don't use real indigo plant anymore as the
manufacturing is complicated yet the color is non-permanent.

Dave S

----- Original Message -----
From: "Keith Gerling" <keith@gumphoto.com>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Thursday, January 22, 2004 10:58 PM
Subject: RE: Indigo

> Indigo is the only pigment I've encountered that flakes whenever I've used
> it on any kind of paper. I'm probably on record as saying that ANY
pigment
> can be used with gum, but the truth is I've never had any success with any
> indigo. Honestly, before I tried indigo, I always wondered what "flaking"
> was when I heard it discussed regarding gum printing. Someone
(Katherine?)
> mentioned here that modern indigo contains lamp black. Maybe that
> contributes to the problem (although I actually haven't had that many
> problems with lamp black on the few occasions I've used it.)
>
> This is what I do to achieve an indigo type color: mix 1 part pthalo blue
to
> 4-5 parts ivory black. It's very close to indigo.
>
> -----Original Message-----
> From: ericawd [mailto:ericawd@mem.quik.com]
> Sent: Thursday, January 22, 2004 9:13 PM
> To: alt-photo-process-l@sask.usask.ca
> Subject: Indigo
>
>
> I am having trouble with achieving the right gum/pigment mix with
indigo.
> I work with gram(s) pigment to ml(s) gum ratios. (e.g.. Windsor Blue 1
> gram to 12 ml). I have tried more than one mix and none have come out
> satisfactory.
>
> Does anyone use WN Indigo and if so what ratio worked?
>
> Candace Spearman
>
>
>
>
>
Received on Thu Jan 22 22:53:34 2004