Motion Picture News (Oct-Dec 1930)

October 11, 193 0 Motion Picture News 37 sound track on combined sound and picture positives shall be as shown in Chart 14. Adopted Definitions Number of Teeth in Mesh. The number of teeth in mesh with the film ( commonly referred to as "teeth in contact") shall be the number of teeth in the arc of contact of the film with the drum of the sprocket, the pulling face of one tooth being at the origin of the arc, as shown in Chart 15. Safety Film. The term "Safety Film," as applied to motion picture materials, shall refer to materials which have a burning time greater than ten (10) seconds and which fall in the following classes: (a) support coated with emulsion, (b) any other material on which or in which an image can be produced, (c) the processed products of these materials, and (d) uncoated support which is or can be used for motion picture purposes irt conjunction with the aforementioned classes of materials. The burning time is defined as the time in seconds required for the complete combustion of a sample of the material 36 inches long, the determination of burning time being carried out according to the procedure of the Underwriter's Laboratory. This definition was designed specifically to define Safety Film in terms of the burning rate of the commercial product of any thickness or width used in practice. The test of burning time, therefore, shall be made with a sample of the material in question having a thickness and width at which the particular material is used in practice. Recommended Practice 1. Aperture Size. The existing ratio of 3 to 4 be STANDARD 16M/M APERTURES PROJECTOR CAMERA 0380 --O Z79"lm 0.1009 ? ~e 10 41 mlm oar T 279 "lm '0/009' tween height and width of picture should be retained when introducing any new size of film. 2. Leaders and Trailers. These should be opaque with markings embossed on them. In a multiple reel story each trailer and the leader immediately following should be marked with the same title. 3. Thumb Mark. The thumb mark on a lantern slide should be located in the lower lefthand corner next to the reader when the slide is held so that the slide can be read normally against the light. 4. Take-Up Pull. This should not exceed 15 ounces at the periphery of a 10-inch reel, or 16 ounces on an 11-inch reel. 5. Projection Lens Height. The standard height from the floor to the center of the projection lens of a motion picture projector should be 48 inches. 6. Projection Angle. This should not exceed 12 degrees. 16M/„ FILM STANDARDIZED SPROCKET SIZES Combination Sprockets A.050/? a NoSpeoorrrTim foots l*af5&**w l*orfs lxaiaS»mo4/*c*fs froesSeimte NumberOfTeeth InCohtact With Film D t M%il.53-Al69l ™%s°3-4 6591 1541 042, 0 043/53% .042 0 0431.53% 039 0 040/52% 5641 6591 1541 0391 0 0401527. 03$ 0 0401.527. 039] 0 0401.52% 5641 653>m 7541 036 O .031/32% 0 03lV52% 036 0 0311.52% sBwho Connors C7D Anno*. 005~Rad. — 08F 7. Standard Observation Port. This should be 16 inches (40.6) square with its center 5 feet 3 inches (160 cm.) above the floor when the projection angle is zero, the center of the aperture to be lowered 1 inch (25.45 mm.) for each one degree drop in angle of projection. 8. Projector Speed. (For 35 mm. Si lents.) The standard practice should be the projection of 80 feet of standard film per minute with a maximum of 85 feet and a minimum of 75 feet. 9. Camera Cranking Speed. (For 35 mm. Silents.) A camera taking speed of 60 feet of standard film per minute with a minimum of 55 feet and a maximum of 65 feet should be used when normal action is desired, in connection with the Society of Motion Picture Engineers' recommended practice of 80 feet per minute projection speed. 10. Projector Lens Mounting. The projector lens should be mounted in such a manner that light from all parts of the aperture shall have an uninterrupted path to the 16m/„ film splices Diagonal Splice l-irVT entire surface of the lens. 11. Projection Lens Focal Length. The focal length of motion picture projection lenses should increase in %-inch steps up to 8 inches and in J^-inch steps from 8 to 9 inches. 12. Projection Objectives, Focal Marks. Projection objectives should have the equivalent focal length marked thereon in inches and quarters and halves of an inch, or in decimals, with a plus ( + ) or minus ( — ) tolerance not to exceed 1% of the designated focal length also marked by proper sign following the figure. 13. Leaders for Sound-on-Film Positive. Manufacturers of sound film should place a leader on each roll of film on which is designated the framing of the picture and the corresponding sound. 14. Projector Apertures for Sound. "Whereas, Investigation has revealed wide variance in theatre projection practices and that there is no effective standard aperture for projection of sound-on-film talking motion pictures ; "Be it resolved: That as a temporary measure this committee recom, mends that all studios and cinematographers using sound-on-film methods make marks on the camera ground glass equally spaced from the top and bottom in addition to the mat mark for the sound track; these marks to delineate a rectangle 0.620 by 0.835 inch in size and that all vital portions of the picture be composed within these limits; "Be it also resolved : That the committee further recommends that theatres which make a practice of reestablishing the full screen proportions from sound-on-film pictures do so by the use of an aperture whose size would be 0.600 by 0.800 inch on the basis of projection on the level, the horizontal center of the aperture coinciding with the horizontal center of the S. M. P. E. aperture." {Continued on next page)