Here’s a simple system for evaluating and controlling print exposure and contrast.
Examine highlight areas and shadow areas separately. Let the exposure
time determine your highlight density and the filter or paper-grade choice
determine your shadows.
Here’s how it works: Make a test strip and an initial print to establish an
exposure time that produces good highlight density—where the light areas
look right—regardless of how light or dark the shadows look. Once you have
a print with good highlights, examine the shadow areas; if they look too light,
make another print with increased contrast, and if they look too dark, make
another print with less contrast. When you change contrast to control the
shadow areas, you may well have to change exposure time to maintain the
same highlight density—depending on your materials and how much of a
contrast change you make.
In examining highlights and shadows, pick important areas that are not
overly bright or dark. Such bright or dark areas often need to be dealt with by
burning-in or dodging, after making your exposure and contrast decisions. For
example, if an area remains too bright even when every other area in the print
looks good, you will probably need to burn it in. Conversely, if an area is too
dark when the overall print looks good, you will probably have to dodge it. Dodging. Dodging is the opposite of burning-in. It allows you to selectively
lighten a specific area of a print by holding back light from that area during the
initial exposure. If you dodge correctly, the rest of the print will not be affected.
Suppose you have a print that looks good overall using an exposure of f/11 at
10 seconds with a #3 filter, but the upper right corner is too dark. Following are
basic instructions for dodging.
1. Place a fresh sheet of printing paper in the easel, and expose it for good overall
exposure and contrast—here, f/11 at 10 seconds with a #3 filter.
2. During that exposure, place a piece of cardboard or other opaque mask under
the lens to dodge (block) light from reaching the area that is too dark (upper
right corner). Dodging times vary widely, but try 10–20 percent of the
initial exposure—here, 1–2 seconds.
During the exposure, the image will be projected on the mask, which can
help you to guide its position for dodging. Move the mask back and forth in
constant motion to blend the dodged area into the rest of the image; otherwise
the dodge will leave a noticeable line. In practice, parts of the image
adjacent to the dodged areas may receive a little less exposure, but if blended
correctly this should not appreciably affect the overall look of the print.
3. Process the print. The results should show the same overall density and
contrast as the initial print—with a lighter upper right corner. If the corner
still looks too dark, make another print and dodge for more time; if it’s too
light, dodge for less time.
To lighten an area moderately, try a dodge of 10–20 percent of the initial
exposure, as described in step 2. If the area needs more significant lightening,
dodge for about 30 percent of the initial exposure (a 3-second dodge for a 10-
second initial exposure). More than 30 percent usually makes the dodged area
of the print look too light, uneven, and/or muddy.
You can dodge an area in the center of a print using a commercially made
dodging tool, or you can make your own by taping a small piece of cardboard
onto the end of a stiff wire handle (such as a straightened paper clip or a wire
clothes hanger). Make several such tools with different pieces of cardboard of
various sizes and shapes.
During the exposure, position the dodging tool so that its cardboard end
blocks light from reaching the area that needs lightening. And again, keep the
entire tool in motion while dodging for even blending with the adjacent image
areas.
Avoid short overall exposure times when dodging. Say that you have an initial
exposure of f/8 at 7 seconds, and you need only about a 10 percent dodge
(.7 seconds) in one area. It’s virtually impossible to accurately time so short a
dodge. So extend the exposure by closing down the lens aperture. Closing it to
f/11 would make an equivalent exposure time of 14 seconds (the smaller opening
allows half as much light through the lens, so requires twice the exposure
time), and closing it to f/16 would make an equivalent exposure time of 28
seconds. A 28-second exposure would permit a more controllable 10 percent
dodge: 2–3 seconds, rather than less than 1 second.
Part VIII: Washing Prints
Once a print is fixed, it sits in the holding bath of water until you are ready to
wash several prints at a time. The main purpose of the wash is to eliminate all
traces of the fixer; inadequately washed prints will stain, discolor, and/or fade
over time.
RC prints don’t require a long wash, because their plastic coating prevents
fixer from sinking deep into the paper fibers. A short running-water wash of
5–10 minutes should do the job. However, fiber-based papers absorb much
more fixer, so they require a far more thorough wash. A plain water wash is not
really adequate; first wash prints for 5 minutes, treat them in fixer remover for
at least 2–3 minutes, and then put them in a final running-water wash for at
least 20–30 minutes.
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