664 



HANDBOOK OF PHOTOGRAPHY 



the block diagram of Fig. 1, involves separate, synchronously operated equipments 

 for recording picture and sound, resulting in two negatives, from which separate 

 prints, known as "dailies" or "rushes," are made for studio viewing and editing 

 purposes. These dual prints are run on synchronized picture and sound projectors. 

 For exhibition, however, the sound and picture negatives are printed on a single 



0,7445"- -> 



O.O/Q!! 





.—-0.868'- 



Gb 



mo.osr'R. 



CD 



-0.050' 



AI76\ 



0.1345" 



Emulsion side up 



Fig. 2. — Standard film dimensions. {Courtesy of Academy of Motion Picture Arts and 



Sciences.) 



film, known as a "composite" or "movietone" print, and shown by means of a com- 

 bined picture and sound projector. 



The standard dimensions of a composite 35-mm. print of this type appear in Fig. 

 2. The camera aperture dimensions, it will be noted, are 0.868 by 0.631 in. The 

 projector aperture is sufficiently smaller (0.825 by 0.600 in.) to prevent showing the 

 frame lines in projection. The latter dimensions therefore represent the working area 

 of the camera field or that portion of the photographed scene which will be shown in 



Blue V 



ole+ 



Bl 

 Srden 



Gr€ en 



ieW 



Red 



400 



450 



500 



550 



600 



Fig. 3. — Division of the spectrum into five colors. 



700 m^t 



the theater. The 4:3 ratio of frame width to height has been found to be satisfactory 

 from an aesthetic standpoint. 



In theater projectors the picture head is located above the sound head, hence, for 

 synchronism, the sound must lead the picture by an appropriate distance along the 

 film, which has been fixed at 18 frames. This displacement is effected in the printing 

 operation. 



Since sound is recorded at a standard speed of 90 in. per min., corresponding to 

 24 frames per second, both photography and theater projection must adhere to the 

 same speed. Higher or lower speeds may be employed in photography, as for slow- 



