SMPTE ST 93-2005 for Motion-Picture Film (35-mm) - Perforated BH.pdf

1、 1 Scope This standard specifies the cutting and perforating dimensions for 35-mm motion-picture film with a BH-type perforation and a perforation pitch of either 0.1866 in or 0.1870 in (4.740 mm or 4.750 mm). 2 Normative reference The following standard contains provisions which, through reference

2、in this text, constitute provisions of this standard. At the time of publication, the edition indicated was valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent edition of the standard

3、 indicated below. SMPTE 223M-2001, Motion-Picture Film Safety Film 3 Dimensions 3.1 The dimensions shall be as given in figure 1 and table 1. 3.2 The dimensions pertain to safety film as defined in SMPTE 223M. 3.3 The dimensions apply at the time of cutting and perforating for film adjusted to a tem

4、perature of 23C 1C (nominally converted to 73F 2F) and a relative humidity of (50 2)%. The manufacturer may indicate other nominal temperature and humidity conditions under which the dimensions apply. 3.4 Dimension H is a calculated value, without corner radii. NOTE The title of this standard was es

5、tablished by the application of a nomenclature system developed for all film dimension standards. Each title provides an indication of the film width, a code designation for the perforation shape (BH, KS, DH, or CS), or the number of rows of perforations (1R, 2R, etc.), depending upon which is the s

6、ignificant factor, or the perforation pitch without the decimal point. Page 1 of 3 pages SMPTE 932005 Revision of ANSI/SMPTE 93-1998 SMPTE STANDARD for Motion-Picture Film (35-mm) Perforated BH Copyright 2005 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 595 W. Hartsdale Ave., White Plai

7、ns, NY 10607 (914) 761-1100 Approved July 13, 2005 SMPTE 93-2005 Page 2 of 3 pages Figure 1 Dimensions Table 1 Specifications Dimensions Inches Millimeters A Film width 1.377 0.001 34.975 0.025 B Perforation pitch (long) 0.1870 0.0004 4.750 0.010 B Perforation pitch (short) 0.1866 0.0004 4.740 0.010

8、 CdPerforation width (diameter) 0.1100 0.0004 2.794 0.010 D Perforation height 0.0730 0.0004 1.854 0.010 E Edge to perforation 0.079 0.002 2.01 0.05 G Perforation misalignment 0.001 max 0.03 max H Perforation chord width (BH perforation) 0.082 calculated 2.08 calculated L 100 consecutive perforation

9、 pitches (long) 18.700 0.015 474.98 0.38 L 100 consecutive perforation pitches (short) 18.660 0.015 473.96 0.38 M Lateral perforation displacement 1.109 0.001 28.17 0.03 R Radius of corners 0.005 max 0.13 max NOTE The metric conversion of dimension A is purposely chosen and shown in three decimal pl

10、aces to prevent the maximum width dimension from exceeding 35 mm. SMPTE 93-2005 Page 3 of 3 pages Annex A (informative) Additional data A.1 The user is reminded that, as a plastic, film can change dimensions temporarily due to moisture or temperature, or permanently due to solvent loss or strain eff

11、ect. A.2 Film for positive use has a longitudinal pitch 0.2% longer than its companion negative. Shrinkage of the negative during aging and processing prior to printing will generally not exceed 0.2%. Thus, the negative stock is expected to be 0.3% 0.1% shorter than the positive. This difference wil

12、l minimize slippage between the two on the 12 in (305 mm) circumference sprocket of the printer, assuming a film thickness of 0.0055 in to 0.0065 in (0.140 mm to 0.165 mm). A.3 The uniformity of pitch, hole size, and margin (dimensions B, Cd, D, and E) are important variables affecting steadiness. V

13、ariations in these dimensions from roll to roll are of little significance compared to variations from one perforation to the next within any small group of consecutive perforations. As an example, the uniformity of the margin is uniquely critical for optical printing. During the printing process, t

14、he placement of the image on the film is usually with respect to successive lateral pairs of perforations at oneframe intervals. During subsequent projection, however, the portion of the image projected is usually located, not by these perforations, but by the edge of the film. The lateral steadines

15、s of the projected image is, therefore, directly related to the frame-to-frame uniformity of the margin. A.4 For historical background on the development of this standard, refer to Miller, A.J. and Robertson, A.C. Motion-picture film its size and dimensional characteristics. Jour. SMPTE, 74: 3-11, Jan. 1965.