the paper of your choice. The results won’t be as finished as with massproduced
photographic papers, which are made with much more consistency
than an individual could hope to match. However, the rough, handworked
quality of liquid emulsion may be just right if you’re trying to achieve a particular
look.
You can use any type of paper with liquid emulsion, though watercolor and
printmaking papers are most suitable. A variety of paper surfaces, tonal colors
(warm or cold), and sizes are available at any good art supplier—and such
characteristics will have an important effect on the final results. Note that you
also can apply liquid emulsion to nonpaper surfaces, such as fabric, wood,
ceramics, glass, and metals; however, you may have to take extra steps, such as
sanding the surface or coating it with polyurethane, to ensure that the emulsion
adheres to some of these materials as well as it does to paper.
Coating paper with liquid emulsion is easy in theory, but challenging in practice.
The basic technique is to brush one or more thin coats onto the paper
surface, let the emulsion dry, and make your print as you would make any photographic
print. But it takes some practice and skill to coat the paper evenly and
well; otherwise the image will show imperfections, streaks, and brushstrokes—
characteristics that some liquid emulsion users actually strive for.
Here are some basic steps for processing paper coated with liquid emulsion.
Read the emulsion manufacturer’s instructions, as some products are different
than others, and experiment:
1. Cover your work surface with paper towels, newsprint, or similar protection
to soak up any spilled emulsion or water.
2. Place the uncoated paper flat on the covered surface.
3. Turn off the room lights and turn on a safelight. Liquid emulsion may be
safely handled in safelight illumination, just like standard photographic
paper.
4. Place the liquid emulsion, in its bottle, in a beaker of hot (120°F) water. At
room temperature, liquid emulsion is a thick gel, and this step will liquefy
it, making it easier to apply. The bottle should remain still in the beaker, as
any agitation can cause air bubbles that may create image defects.
5. Wet a clean, soft brush with emulsion from the bottle and spread a thin
layer over the paper as evenly as you can manage. Or try pouring a small
amount (about the size of a quarter for an 8" x 10" sheet) in the center of
the paper and use the brush to spread it out. Often you will need only one
coat, but very porous papers and other materials might need two coats or
more. Don’t overcompensate by applying the emulsion too heavily.Make your brushstrokes all in one direction. However, if you apply more
than one coat, apply the second coat perpendicular to the first one. Allow
the previous coat to become slightly tacky before recoating the paper. You
can coat a number of sheets at a time and store them in darkness for use
later, but you should try to use them within a day or two.
6. Dry the coated paper. You can leave the paper flat or hang it up on a line,
using clothespins. Drying can take 30 minutes to several hours, depending
on the heat and humidity in the room. Turn off all lights while liquid emulsion
dries to prevent fogging (unwanted exposure).
7. Set up your negative in the enlarger, much as you would when working
with any photographic paper.
8. Expose a sheet of dry, coated paper. It’s best to start with a test strip. Expect
longer exposure times than with standard photographic papers since
paper coated with liquid emulsion is less sensitive to light. And take extra
care not to scratch or otherwise physically damage the surface of the paper,
as liquid emulsion is relatively fragile, even when dry.
9. Process the exposed paper. You can use a standard print developer, but
rinse the paper with water after the developer instead of stop bath; the stop
bath can harm the emulsion. Finally, use a standard fixer (with hardener)
to fix the image. These times are recommended:
Developer 2–3 min
Water rinse 1⁄2–1 min
Fixer 15 min
10. Wash the print in running water for about 5 minutes after the fixer. Then
use a fixer remover for about 3–5 minutes, followed by a final wash for at
least 30 minutes in cool running water.
11. Air dry the washed prints on drying screens or by hanging them up.
Processing nonpaper surfaces and three-dimensional objects coated with
liquid emulsion requires similar steps, though specific techniques may need
modification. Use a brush or sponge to apply the processing chemicals, and
wash the surfaces in the same manner as paper, working gently, but continuously.
Alternatively, you can immerse coated objects in buckets of processing
solutions.
Note that you can tone or hand color liquid-emulsion prints if you choose.
But do so with care to avoid physical damage. A thin coat of polyurethane,
available at hardware stores, painted or sprayed over the paper surface may
help make the image more permanent.
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