The screen and its position are controlling factors in the planning of a motion picture theatre. Since the screen is the focal point for the audience, the general design and decoration of the interior should aim to concentrate attention on that point.

Position Of Screen

The position of the screen is largely influenced by the quality of pictures desired. For ordinary front projection a screen should be located eighteen or twenty feet behind the proscenium opening to give a shadow box effect when the stage is darkened. The farther behind the opening the screen is placed the better, but great care should be taken not to install it so far back that spectators sitting on the extreme sides of the auditorium would be deprived of a full view of the screen.

Screen For Rear Projection

Probably the best screen for use in a motion picture theatre where conditions will permit is a translucent screen for rear projection, where the picture is thrown from behind instead of from the front. Rear projection requires a space of about fifty feet between the machine and screen for good effect, although some arrangement might be perfected for diminishing that distance by the use of an intermediate mirror for reflecting the picture between the machine and the screen. In the use of either front or rear projection, the screen should be raised about two feet above the stage level so as to present a perfect view from every seat in the house. Any extraordinary lifting of the eyes to view a picture soon tires the optic nerve and produces drowsiness.

Brilliant Picture Desirable

As regards visual requirements, the tendency is now toward smaller and better lighted pictures. The size of a picture depends upon the distance of the throw and the amperage of light. A twelve-foot picture is considered "life size." A well lighted picture of this size should be the limit for a fifty-foot throw, a fifteen-foot picture for a seventy-five foot throw, and for a hundred-foot throw or longer any size that may be brilliantly illuminated and that will not show living figures that appear from the rear seats much larger than normal.

The following table Copied from Richardson's Motion Picture Handbook, an invaluable text book for managers and operators, will furnish a scale of relative widths and heights, together with the greater cost of producing larger pictures:

Light Table

Width in feet.

Height in feet.

Area sq. ft.

Area increase in sq. ft.

Percentage of increase area.

6

4.40

26.4

• • • •

• •

7

5.13

35.9

9.5

36

8

5.87

36.9

11.0

31

9

6.60

59.4

12.5

26

10

7.33

73.3'

13.9

23

11

8.07

88.7

15.4

21

12

8.80

105.6

16.9

19

13

9.53

123.9

18.3

18

14

10.27

143.7

19.8

16

15

11.00

165.0

21.2

15

16'

11.73

187.7

22.7

14

17

12.47

212.0

24.2

13

"18

13.20

237.6

25.6

12

19

13.93

264.7

27.1

11

20

14.67

293.3

28.6

11

While it may require a stronger light to project a picture through an indirectly lighted auditorium the result is well worth it, especially with comedy pictures. Even with drama, darkness does not really increase the interest, a dimmed light being preferable to none at all. Just so radically as the motion picture differs from the spoken drama, so must the manner of its presentation show innovations in stagecraft.

Materials For Screens

There are many good and some bad screens on the market today. There can be very little objection to a screen of hard plaster laid on metal lath and mounted on a frame of non-combustible material. Such a screen affords more rigidity than a cloth screen, which is susceptible to atmospheric disturbances. The above refers only to screens for ordinary front projection. The best screens for rear projection are made from ground glass, a rigid substance that permits of various surface treatments.

Screen Surfaces

There is, however, a great difference in screen surfaces. Much depends upon the use to which the screen is subjected. The function of a screen is to reflect light, and light rays always travel in straight lines. If the screen has a matte or roughened surface, instead of a polished one, a decided advantage is obtained, as the light rays are slightly diffused in reflection and a better picture is the result.

For a wide house a special surface that will distribute the rays at a wider angle is desirable, while for a narrow house a more brilliant surface that concentrates the light is better. The exposed surface of all screens should be outlined with a dull black border to give better definition and impart a beneficial effect to the picture. This border should be painted with ordinary dry lampblack mixed with a preparation of one-third linseed oil and two-thirds turpentine.