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1954-55 Theatre Catalog, 12th Edition, Page 272 (236)

1954-55 Theatre Catalog, 12th Edition
1954-55 Theatre Catalog
1954-55 Theatre Catalog, 12th Edition, Page 272
Page 272

1954-55 Theatre Catalog, 12th Edition, Page 272

mend the proper focal length lens to give the desired picture width.

After determining the proper focal length lens, the projector aperture plates should be filed so as to project the proper shaped picture to meet the size of the screen that has been selected. If the screen carries black masking, the projected picture image should overlap the masking far enough to give a well framed picture.

Much has been said both for and against the practice of gaining proper picture shape by diminishing the opening in the projector aperture plates. The procedure is called ticroppingfi Our desire is to gain the best picture quality, and as long as cropping gives the best picture quality, we recommend cropping.

In considering cropping, most people think of a possible quality loss from the cropped print. The fact is that real loss is due to the restricted area of negative that is used to gain the cropped picture. The VistaVision negative is large, thus the loss does not occur with VistaVision. A loss does occur on e-the 2.55:1 anamorphic pictures when the aspect ratio is reduced by side cropping, and

EXAMPLES of the diiierent aspect ratios are illustrated here. Compare the old 1.33 to 1 ratio (top, leit) with VistaVision aspect ratio. Then compare


some loss does occur when pictures made from standard negatives are cropped.

ttCroppingii is accomplished in the projector by using special projection aperture plates filed to the desired aspect ratio.

We make no specific recommendations in regard to projector type or projector lamp houses, except that in our experience with shorter focal length lenses, better screen illumination is obtained with lamp houses of the reflector type having mirrors 16 inches in diameter.

In theatres using very large lamphouses and high amperage, we recommend the use of water and air cooling, also dichroic heat reflectors.

Variable Prismatic

Expander Lenses

There is a great deal of confusion between aspect ratios and squeezed and/or expansion ratios. The aspect ratio is the ratio of width to height of the picture image on the screen, and/or the Width to height of the picture image on the film. The squeezed and/or expansion ratio is the result of an optical change in a lens system. When the images are

Paramount Pictures Corporation,

WAT 1.85/1 mm

with: full Advantagn at Marina. $tnen Height and Width! i

squeezed they are made to appear thin and tall. When these thin and tall images are expanded in projection, they appear normal on the screen. .

In the CinemaScope system thecamera lens picks up a scene that is 2.66 times as wide as it is high. This scene is squeezed horizontally in the squeeze ratio of 2:1, which gives a negative image in the aspect ratio of 13321. A print made from this negative is still squeezed. ' H:

In CinemaScope projection, the image passes through an anamorphic expander lens which expands the image in the ratio of 2:1. This would normally give a screen aspect of 2.66:1. In the CinemaScope process the sides of the picture are cropped down to make room for the magnetic stereophonic sound tracks, so that the final aspect ratio of the picture when projected is in the ratio of 2.55:1.

In the VistaVision process, standard camera lenses are used in photography and a standard large negative image is obtained: When desired, squeezed.) prints are made during the process of optical printing, but in the case of VistaVision the squeeze ratio is 11/21. When these prints are projected, they must be pro the.2.55 to 1 ratio aspect ratio (top, right). It is up to the individual to decide it the VistaVision ratio of 1.85 to 1 gives the clearest picture.

...A PIBWRE AT THE RAIN) 2.55/1;

1954-55 Theatre Catalog, 12th Edition, Page 272