The terms
"A" and "B" wind properly refer
to the manufacturer’s winding of single perforated
16mm raw stocks. These terms have also become widely
used to designate the emulsion position of both
16mm tracks and picture elements. Because of this
widespread usage with reference to emulsion position,
it is important that it be explained.
(Figure 12 - A-Wind and B-Wind) Contact
Printing
In contact printing, emulsion to emulsion, the
image position of the finished material is always
opposite of the image position of the printing
material. The wind of the film alternates from
"A" to "B" or "B"
to "A" in each succeeding generation.
In contact printing of titles, make sure your
title is in the same emulsion position as the
preprint material that you are using.
Optical
Printing
In optical printing it is possible to print the
picture in either the same image position or in
the opposite image position of the preprint material.
When ordering materials to be made optically,
you must specify the wind you require, either
"A" or "B", of the material
to be made.
16mm
Prints
A 16mm positive print can be either "A"
or "B" wind. A print projected with
the emulsion away from the lens is "A"
wind, and with the emulsion toward the lens, "B"
wind. "A" wind prints and "B"
wind prints require different focus positions
of the projector lens and, therefore, should not
be spliced together.
35mm
Prints
"A" wind and "B" wind terminology
is not used in 35mm, although the same changes
in emulsion position occur. This is possible because
35mm printing follows an exact set of standards
in which negatives, whether original, duplicate
negatives or CRI’s, all read through the
base.
35mm master positives always
read through the emulsion. A standard 35mm release
print reads through the emulsion, and is projected
with the emulsion towards the light source.
When making 35mm prints or intermediates,
the proper emulsion position is maintained automatically
by contact printing emulsion to emulsion. The
only exception is in making a CRI, and to maintain
the proper emulsion position the CRI must be printed
optically or with base to emulsion in a contact
printer. If this must be done, a specular light
source in the contact printer will help to maintain
sharpness. topˆ |
