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.
Projector Systems
The Film Track
The route taken by the film as it travels through the projector from spool to spool is known as the film track. Fig. i shows the film track of a typical silent projector. You will notice that the film is drawn from the feed-spool by the feed sprocket-wheel, after which a loop is made in the film before it passes through the gate where it will be moved in a series of jerks by the intermittent mechanism. Below the gate is another loop, after which the film is again pulled at an even speed by the first take-up sprocket-wheel. The film then continues, perhaps via one or more guide rollers, onto the take-up spool.
In a sound projector, however, the film would be taken through the sound-head after leaving the gate, and then on to the take-up spool. The sound-head is the place where the business of scanning the photographic sound-track takes place. (See Fig. 6).
The film track, then, consists of the picture-gate, sound-head, two or more sprocket-wheels and a number of guide rollers, the whole forming the "operating side" of the projector. The opposite side is known as the non-operating side (not right or left) and the front of the projector is the end in which you will find the projection lens. And the back of the projector is the "rear". Remember these apparently naive instructions and you won't get lost . . .
The Optical Systems
Every projector consists of a number of systems, which may be examined separately in order to get a clear idea of their respective functions. Most important, of course, is the optical sys
24