1. What papers do what from a image quality standpoint.
2. What developer combinations work or don't
I'll mostly print cyanotype, but may occasionally may print gelatin
silver.
any thoughts out there?
- Mike -
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Mike
Paper negatives work well for a number of processes, particularly for gum.
As exposures are a lot longer than for film negs, three times as much or
more, I use three paper negs when making a gum print requiring a wide
contrast range. One for the highlights; one for middle tones and one for
the shadow detail. These are made by giving the paper progressively longer
exposures under the enlarger, where the positive is reversed to give a
'wrong reading' negative as you will need to expose through the back when
making your print.. It is easy to register each with the others on a light
box using a couple of pins. These registration marks are then made onto the
print so that the appropriate range negative can be used for each exposure
on a gum print.
This system is fine for gum where you can make a separate exposure for each
range of tone as exposures are relatively short as only a small range of
tone is used for each exposure, but if you want to get a full range of tone
for a process where only one exposure is the normal practice, you will need
to use the very dense negative which, for gum printing, is the one used
for the shadow detail. Such a negative when used to make a cyanotype,
depending on your UV source, is likely to need exposures measured in hours
rather than minutes.
It is possible to reduce the exposure by using only the emulsion layer
stripped from the paper backing.
You will need a grade 1 resin coated paper, to maintain gradation,
developed in your usual paper developer. RC papers lie flat.
While it is possible to make large film negs by contacting from your
prints, could you explain the advantage that would be gained by using a
paper neg to print onto silver gelatine?
Hope this helps.
Terry