light-sensitive materials, and lighting conditions
commonly used in your facility; for example, when
awards presentations are commonly photographed
using syncro-sun techniques with a medium-format
camera and Kodak VPS film, then your standard
negative should be taken under the same conditions. The
same applies for studio portraits, indoor on-camera flash
photography, and so forth. A basic enlarger filter pack
should be determined for each negative.
TRIAL-AND-ERROR PRINTING
Few characteristics are exactly the same in two
color negatives. Even when the subject matter is similar,
differences can be caused by normal manufacturing
variations from one emulsion to another, adverse
conditions before exposure, illumination of different
color quality, variance in sensitivity with changes in
illumination level and exposure time (reciprocity
effect), adverse storage conditions between exposure
and processing (latent image loss), and nonstandard
processing conditions.
Most color negatives of the same subject that are
exposed under similar conditions print similarly, but not
identically. Differences may result from variations in
lighting conditions (time of day, sky conditions, etc.),
film emulsions, film processing, or other factors. These
differences are normal and should be expected. The
standard negative provides a good starting point for
future printing requirements.
For example, you made an excellent 8x10 print
from the standard negative with a filter pack of 40M +
60Y and exposed the print for 10 seconds at f/5.6. The
enlarger settings should remain the same as a starting
point for similar negatives, providing the same type of
paper is used. For a particular production negative, you
may find it necessary to add a 10M filter to the pack and
adjust the printing time to 11 seconds to compensate for
the differences between the new negative and the
standard negative. In other words, the new negative may
print differently from the standard negative by a 10M
filter and a 10-percent increase in printing time.
The amount and types of color equipment you use
depend on the volume of color production of the
imaging facility where you work. A photo lab that makes
occasional color prints probably uses only a standard
negative and color printing viewing filters. Larger Navy
imaging facilities that produce large quantities of
custom color printing may use evaluation methods
involving instruments, such as color analyzers,
densitometers, and other electronic devices.
COLOR ANALYZERS
Color analyzers operate by comparing a standard
negative to production negatives. For successful
negative evaluation, the reference areas must have the
same subject matter in all the negatives; for example, a
gray card included in the picture, a flesh tone, the
highlighted area of an aircraft wing, or a neutral area of
a ship, all provide a suitable reference area. In
portraiture, a medium-flesh tone is often selected In
other fields of photography, you should either include a
gray card in the scene or expose an additional negative
replacing the subject with a gray card. In the latter case,
the negative with the gray card is used only for
evaluation purposes and is replaced by the subject
negative when the print is made.
When a skin tone is used instead of a gray card in
portrait negatives, the color analyzer tends to reproduce
all skin tones the same as the standard negative
regardless of variations in skin color or lighting.
Similarly, all images of a gray card tend to be printed
alike regardless of the position of the card relative to the
main light.
Color analyzers are used to reduce the waste that is
produced through the trial-and-error method of color
printing. The standard negative is used as a reference
when color analyzing instruments are used. There are
two categories of color analyzers: off-easel and on-
easel.
Off-Easel Analyzers
Off-easel color evaluation is performed by
measuring or evaluating the color negative before it is
placed in the enlarger. Commonly in Navy imaging
facilities, off-easel evaluation is accomplished using a
densitometer. The main advantage of using a
densitometer is you can service a number of enlargers.
That is especially useful when you cannot have on-easel
analyzers for each color enlarger. Another advantage,
off-easel evaluation can be done under normal room
lighting conditions.
To set up an off-easel evaluation system, you must
first read the density of the reference patch from your
standard negative on a transmission densitometer. You
read the reference patch through a red, green, and blue
filter. The densitometer provides you with direct density
reading of the cyan, magenta, and yellow dyes present
in the reference patch. The values that you read from the
reference pack are then added to the known standard
negative filter pack of the enlarger. The production
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