Drive-Ins.com
> > > >

1954-55 Theatre Catalog, 12th Edition, Page 318 (282)

1954-55 Theatre Catalog, 12th Edition
1954-55 Theatre Catalog
1954-55 Theatre Catalog, 12th Edition, Page 318
Page 318


1954-55 Theatre Catalog, 12th Edition, Page 318

that few 3-D audiences have ever enjoyed. With the two-projector system, even at its best and under ideal operating conditions, it is a rare show that goes off without a hitch of some sort. Even with synchronization correct, there has almost always been some difference in light output between the two projectors; audiences have often had in effect a daytime picture in one eye and a night-time picture in the other, an experience far from relaxing. Aside from this, there have been other difficulties harder to remove or correct: One picture has often been a trifie larger than the other because of a small mismatching of focal lengths of projection lenses; a slight weave and jump of the film in the individual projectors has had the effect of pulling the three-dimensional space this way and that, forward and back.

All theseltroubles disappear when the two images run on a single film through a single projector.

Problems Solved

Another problem that should be disposed of when Vectograph film is made available, is the problem of screen brightness together with the closely related problem of picture sharpness. Unlike any other single-film system that has been proposed for the projection of 3-D motion pictures in full color, Vectograph film uses the entire film area, instead of only one half of each frame, for each of the two images required for 3-D. Instead of two half-sized images placed side by side or one above the other within the frame, two full-sized images are superimposed one over the other.

This means twice as much film area available for each image, twice as much light on the screen for a given light

source, and twice as much area for

achieving picture definition.

These factors are of the highest importance in connection with the longpromised "marriage" of 3-D and widescreen techniques. One of the goals of TechnicolorePolaroid development is a standard of picture quality which promises to make the marriage a happy one.

U nusual Properties

The unusual properties of Vectograph film are based on the fact that the images are rendered in terms of degree of polarization of the light transmitted through the image. The images are not made in any of the ordinary ways, from opaque pigments like lamp black, for example, or metallic particles like the silver grains of photography. The images, instead, are intrinsically light polarizers.

The invention is the work of Edwin H. Land, President and Director of Research at Polaroid Corporation and inventor of modern sheet polarizing materials, in collaboration with Joseph Mahler.

A singular property of polarized light allows the two images to be superimposed without interfering with each other.

Ordinary light is made up of a helterskelter mixture of vibrations lying in all possible directions crosswise to the direction of the beam. After it has passed through a polarizer, these vibrations can

THIS diagram helps to explain how the Polaroid Vectograph system of single strip 13-!) operates.

be visualized as an orderly array of flat ribbons, all parallel with each other and all lined up with polarizing axis or ttoptical grain" of the polarizer. These ribbons can be visualized as passing easily through a second polarizer if they are all lined up with its optical grain.

When you look at a perfect light polarizer through another polarizer, it will appear essentially black if the polarization axes of the two polarizers are crossed at right angles. The ribbons cannot pass through ffacross the grain." The second polarizer will be clear and practically invisible, however, if the vibration directions of the two are lined up parallel to each other. This fact can be demonstrated easily with two polarizing filters.

If the polarizer you are looking at is not perfecteif it is only polarizing part of the lighteit will appear grey, not black, when your viewing polarizer is crossed with it. It will be darker or lighter as its degree of polarization is greater or less. It will still be invisible, nevertheless, if the viewing polarizer is lined up with it.

For presenting three-dimensional pictures, both sides of the Vectograph film are employed. On each side, printing solutions are employed to set up an image in terms of polarization-a high degree of polarization for areas which are to appear dark, a low degree of polarization for areas which are to be light. This control of the degree of polarization determines the point-t0point density of the images when they are seen through polarizing viewers. It creates the pictures in terms of percentage of polarization.



VECTOGRAPH FILM IS A COMPLETE. SELF-CONTAINED STEREO MATERIAL, WHICH MAY IE VIEWED DIRECTLY OR PROJECTED IN A STANDARD

PROJECTOR WITH NO ATTACHMENTS





THIS IMAGE APPEARS IN FULL CONTRAST TO LEFT EYE - INVISIBLE TO THE RIGHT EYE

.\\\\\\\\\\\\\\i\\\\

\\\\\\\ \\\\\\\\\\\\\\\\\IIh



RIGHT EYE

LEFT EYE



THIS IMAGE APPEARS IN FULL CONTRAST TO RIGHT EYE - INVISIBLE TO THE LEFT EYE

THEATRE CATALOG 1954-55
1954-55 Theatre Catalog, 12th Edition, Page 318