ISO 491:1995

INTERNATIONAL
ISO
STANDARD 491
Fifth edition
1995-04-01
Cinematography - 35 mm motion-picture
film and magnetic film - Cutting and
perforating dimensions
Cinkma tographie - Film cin6ma tographique et magnktique de
35 mm - Dimensions de coupe et de Perforation
Reference number
ISO 491: 1995(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide
federation of national Standards bodies (ISO member bodies). The work
of preparing International Standards is normally carried out through ISO
technical committees. Esch member body interested in a subject for
which a technical committee has been established has the right to be
represented on that committee. International organizations, governmental
and non-governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission
(1 EC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 491 was prepared by Technical Committee
lSO/TC 36, Cinematography.
This fifth edition cancels and replaces the fourth edition (ISO 491:i 988)
of which it constitutes a technical revision.
Annex A forms an integral part of this International Standard. Annexes B
and C are for information only.
0 ISO 1995
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronie or mechanical, including photocopying and
microfilm, without Permission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-l 211 Geneve 20 l Switzerland
Printed in Switzerland
ii
INTERNATIONAL STANDARD 0 ISO ISO 491:1995(E)
Cinematography - 35 mm motion-picture film and
magnetic film - Cutting and perforating dimensions
3 Conditions for the measurement of
1 Scope
ciimensions
This International Standard specifies the cutting and
perforating dimensions for 35 mm unexposed
The dimensions and tolerantes specified in this Inter-
motion-picture film and 35 mm magnetic film, and the
national Standard apply at the time of manufacture,
types of perforations used.
measured under atmospheric conditions of
(23 + 1) “C and (50 k 5) % relative humidity, as
specified in ISO 554Y A manufacturer may indicate
other nominal temperatures and humidity under
which dimensions apply.
2 Normative references
4 Dimensions
The following Standards contain provisions which,
through reference in this text, constitute provisions
4.1 Dimensions of motion-picture film
of this International Standard. At the time of publi-
cation, the editions indicated were valid. All Standards
The dimensions shall be as shown in figures 1 and 2
are subject to revision, and Parties to agreements
and given in table 1 (in millimetres). They apply to un-
based on this International Standard are encouraged
exposed motion-picture and magnetic film which
to investigate the possibility of applying the most re-
conform to ISO 543. These specifications apply at the
cent editions of the Standards indicated below.
time of cutting and perforating.
Members of IEC and ISO maintain registers of cur-
rently valid International Standards.
4.2 Dimensions of magnetic film
ISO 543: 1990, Photography - Photographit films -
With regard to 35 mm magnetic films, the dimensions
Specifica tions for safety film.
which apply are those specified in table 1 under the
ISO 554: 1976, Standard atmospheres for conditioning designation “Type P” with a Perforation pitch B and
and/or tes ting - Specifica tions. the length of any 100 consecutive intervals L.
1) All measuring instrument calibrations should be referred to a temperature of 20 “C (as specified in ISO 1 Ul) and a relative
humidity of 50 %.
0 ISO
Table 1
Dimensions in millimetres
Dimension Type DH
Type P Type N
A 34,975 + 0,025 34,975 + 0,025
34,975 + - 0,025 - -
B 4,75 + 0,Ol 4,75 + 0,Ol 4,75 + 0,Ol
- - -
B’ 4,74 + 0,Ol 4,74 + 0,Ol
- -
c 2,800 ‘;r;y; 2,800 ‘in;:; 2,800 ‘;fy;
1,850 ‘;#;;;
D 1,98 + 0,Ol 1,850 :;f;;
-
,
2,Ol + 0,05
E 2,Ol + 0,05 - 2,Ol + - 0,05
-
28,17 + 0,05
F 28,17 + 0,05 - 28,17 + - 0,03
-
0,025 max. 0,025 max. 0,025 max.
G
2,08 nom.
H
0,500 :;j;; 0,13 max. 0,33 + 0,03
R -
,
L 475,0 + 0,4 475,0 + 0,4 475,0 + 0,4
- - -
L’ 474,0 + 0,4 474,0 + 0,4
- -
NOTES
1 While present usage is that type N perforations may be employed for Camera and intermediate films and type P per-
forations for print films, the long-term objective should be for all 35 mm films to have type P perforations.
2 Dimensio
...