Réf. : Re: Gum dichromate issue

 
I am also writting a book on negative separation for the alt process
http://users.skynet.be/philippe.berger/livre1.jpg
 
Philippe
 
-------Message original-------
 
De : alt-photo-process-l@sask.usask.ca
Date : Wednesday, August 11, 2004 21:48:29
A : alt-photo-process-l@sask.usask.ca
Sujet : Re: Gum dichromate issue
 
Sandy,
 
Thanks for your advices.
I got some of he books you told me and they are helpful.
Do you know about other books on negative separation?
Yes, you are right I will only do it by computer but if you don't understand
well the process then you won't be able to do it well.
For instance, I always have a print that requires an adjustment or reprint.
How would you do it? Why it always happens with a specific print? Is it the
pigment or is the specific negative layer?
By the way, when you reprint the cyan and you are following Sam Wang paper
do you do it again on cyanotype? Not with gum?
 
Giovanni
 
 
----- Original Message -----
Wrom: QBGJSNBOHMKHJYFMYXOEAIJJPHSCRTNHGS
To: <alt-photo-process-l@sask.usask.ca>
Sent: Monday, August 09, 2004 11:18 PM
Subject: Re: Gum dichromate issue
 
 
> There were more than a few full books put out on making separation
> negatives for the graphic arts. If you like I will try to provide you
> with full citations. I know there is at least one very good one in my
> university library and I suspect that if you do a search on a good
> public or university library in your country you will find the same.
>
> However, as someone who has actually made three-color carbon and
> carbon prints with film separations let me assure you that it takes
> a lot of time. There is no way in the world I would every think of
> doing that kind of work again without making digital separations on
> the computer.
>
> Sandy
>
>
>
>
> >
> >
> >> I do have several questions and probably too many but the first is:
> >> Is there any book you recommend me to read that deals with the three
> >> negatives instead of the Kodak single color negative?
> >
> >Good question. The best books on separation practice I recall were short
> >things put out by Kodak that were out of print long ago. I'll look
through
> >my photo books and see what I can find. First, you have to separate the
> >colors. Are you intending to make three in-camera negatives, or shoot
> >color film (or digital) and do the separation later?
> >
> >The basic issues are (i) getting the color balance right, which is a
matter
> >of using the right filters and choosing the right exposure and
development
> >for the three negatives [with DT, one often develops the 3 negs to
> >different contrast levels -- I suspect the same may be true of other
> >processes]; and (ii) registration of the three [or four, with a luminance
> >layer] negatives. In the old days, we punched holes in unexposed film
and
> >used pin-registered film holders, enlarger negative holders, and printing
> >frames throughout the process. Condit, the manufacturer of
> >pin-registration equipment, went out of business a few years ago. I
> >understand that shrinkage is a factor with multi-layer gum, so
registration
> >may be more of an issue for you than it is for DT printers.
> >
> >Best regards,
> >
> >etienne
>
>
 
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