nearly every learning/training situation. While it is usually not practical
to disassemble a jet engine in the classroom, drawings, diagrams, and
photographs of disassembly steps are effective substitutes when accompanied
by oral explanations.
Thus, you have a visual information learning
situation. It has been proven that the educational value of any lecture is
enhanced by the inclusion of graphs, charts, maps, or original scenes in
slide form.
PART A - SLIDE DUPLICATING FILMS AND EQUIPMENT
1.
Duplicating Film.
a. Selecting the Film.
In selecting the film to duplicate color
slides, your first choice should be a film designed specifically for that
purpose, such as Kodak duplicating film 5071. Duplicating film has a wide
exposure latitude producing good density slides even with slight over or
underexposure during copying.
(1) If this film is unavailable, you may use the same film used to
produce the original or any other color reversal film that is compatible
with the camera, processing, and lighting that you are using.
However,
color reversal films that are not specifically designed for copy or
duplication work present problems because they do not control reproduction
contrast well, resulting in duplicates that are too contrasty.
(2) Also available are internegative films for making internegatives
from color transparencies and for making direct copy negatives from color
negatives (this was discussed in lesson 1). Black and white negatives can
be produced from color transparencies as well.
A full scale panchromatic
film should be used.
b. Importance of Temperature Light Source.
When working with color
reproduction material, you must keep in mind the temperature of the light
source that will be used to illuminate the transparency for copying.
(1) The Kelvin temperature of the film must match that of the light
source. If it does not, a shift in color reproduction will result in the
duplicate transparency.
If, for example, the exposing light source is
electronic flash, daylight balanced color film can be used.
(2) If two light sources are used, the dominate source must match the
film. Even when the Kelvin temperature of the primary light source and the
film are matched, color shift sometimes occurs.
This is due to the
difference in Kelvin temperature of various exposing light sources, and the
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