- Wayde
(allen@boulder.nist.gov)
---------- Forwarded message ----------
Date: Mon, 2 Sep 1996 11:45:45 -0500
From: S. Carl King <sanking@hubcap.clemson.edu>
To: "J. Wayde Allen 303-497-5871" <allen@boulder.nist.gov>
Subject: Re: My First (Unsuccessful) Carbon Print
Dave,
I just read my mail today and don't have a lot to add to the advice
that others have already offered. In addition to Nadeau's book on
carbon printing there was a good article in View Camera several years
back which would be good reading and could help you a lot.
Sandquist, Michael. "Carbon Printing." View Camera, Nov./Dec.
1990: 4-11).
It is difficult to know exactly what is going on with your printing,
but I will rejoin some of the points previously addressed by Wayde,
Pete and Klauss.
>> What I
>> noticed is that even after several minutes soaking in warm water (about
>> 100F), I didn't see the pigment oozing out as described in books.\
>
>Hmmm ... you could try increasing the temperature to say 110F, and see if
>that helps. I also seem to recall that a drop or two of ammonia in the
>water will soften the gelatin. Check in Crawford's, Keepers of Light book.
I don't think the temperature is the problem. 100F is warm enough for a
7% solution of the Knox gelatin you are using, so if there is no
pigment oozing out it means either that the image was way overexposed,
causing all the gelatin to harden, or that the tissue was not correctly
sensitized, or as Wayde suggests,"you didn't get enough pigment in the
gelatin so the light is penetrating all the way through the pigment
layer."
>> Another question is related to the sensitizing of the pigment tissue. How
>> long should I should the tissue in the sensitizer (I am using Pot.
>> dichromate). I noticed that after some soaking, the gelatine of the tissue
>> starts to dissolve. Is this normal?
This is definitely not normal. You have either used too strong a
solution of senzitizer, or it was much too warm (these variable play
against one another). If the room where you work is at 65-70F use a
senzitizer at no more than 60F, and down to 50F is even safer.
>>> Also, does anyone know if there is any weekend worshop on carbon
printing?
>No, at least not in the US. Sandy King has said that he would be willing
>to teach such a seminar, and there was another guy in California that also
>was interested.
I have done some weekend workshops in the past. Anyone who is
interested and is willing to travel to South Carolina should contact me
off list. I have also considered the possibility of doing a 3-5 day
workshop on pigment printing at Clemson University, perhaps in
conjunction with my colleague Sam Wang. Again, let me know if you are
interested.
Sandy King
Sanking@hubcap.clemson.edu