We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
154
RICHARDSON'S BLUEBOOK OF PROJECTION
(31 ) To know what kind of screen surface is best for your theatre you must know all the viewing angles. This may be ascertained by following Fig. 49, which is laid out in squares. Measure the inside dimensions of your auditorium. Each one of the vertical lines represents a ten-foot width. Each horizontal line represents ten feet of depth. If your auditorium measures 40 feet wide by 70 feet deep, you have only to count back from the screen to the seventh horizontal line in Fig. 49. Then count to the second vertical line on each side of the center line and you have your theatre floor plan laid out in the diagram.
Suppose your seating takes in the full width of the theatre — no side aisles — and that it comes within 15 feet of the screen and within 8 feet of the rear wall. That calls for a screen of high diffusing power, since a considerable number of seats will be beyond the 40 degree angle, many outside the 50 degree angle and a few even outside the 60 degree angle. It's a bad condition for two reasons : first, the best available screen surface cannot distribute light over so wide an angle without perceptible fadeaway, and secondly, it creates heavy visual distortion from the front side seats.
(32) Those seated at a heavy horizontal angle to the screen surface see all objects thereon as abnormally tall and thin. When an object we always see in certain proportions of width and height is suddenly reduced in width, it then appears to be taller than it really is. Examining Fig. 50 we see an object of a certain width
Fig. 49. — A straight edge laid on any of the lines will touch the side of the screen opposite. Anyone seated within the angle formed by these lines has a proper viewing position in relation to the screen.