American Cinematographer - October 1968 - 50

the film has two rows of perfora¬
tions, and "3000" indicates the pitch
of the perforations as expressed in
decimal inches: 0.3000 inch. (Note:
ASA frequently revises these stand¬
ards so it is wise to check if a later
spec sheet is available which includes
modifications.)

using film perforated to this standard
should have a single pull-down claw.
Duplicating or printing films intended
for sound applications with optical
tracks or magnetic striping are also
perforated to this standard. Its physi¬
cal size and shape are identical to
16mm film perforated with two rows.
American Standard PH22.110-1965
Dimensions for 16mm Motion Picture
Film. Perforated Two Edges-2R-2994
(Short Pitch). This perforation is used
primarily on professional motion pic¬
ture films where duplicate prints will
be required.
American Standard PH22.109-1965
Dimensions for 16mm Motion Picture
Film. Perforated One Edge-1R-2994
(Short Pitch). Same as above, except
one row of perforations.

Standard 16mm Perforations
American Standard PH22.5-1964
Dimensions for 16mm Motion Picture
Film. Perforated Two Edges-2R-3000
(Long Pitch). This perforation is used
primarily on all 16mm products for
both original camera use and dupli¬
cating purposes. It is rectangular in
shape with fillets in the corners.
American Standard PH22.12-1964
Dimensions for 16mm Motion picture
film. Perforated One Edge-1R-3000
(Long Pitch). This perforation is used
on original camera films mainly for
single-system sound pictures or post
magnetic sound recording. Cameras

35mm Films
35mm motion picture films are sup¬
plied in both long and short pitch per¬
forations. The perforation itself is

35mm FILM DIMENSIONS
NEGATIVE FILM

TYPES OF PERFORATION

t<-c-*(

FILM
35mm,
35mm,
35mm,
35mm,
35mm,
35mm,

ASA STAND.

BH-1870'
BH-18662
KS-18703
KS-1866
DH-1870
CS-1870

A
1.377
1.377
1.377
1.377
1.377
1.377

PH22.34
PH22.93
PH22.36
PH22.139
PH22.1
PH22.102

B
.1870
.1866
.1870
.1866
.1870
.1870

C
.1100
.1100
.1100
.1100
.1100
.0780

►-c

POSITIVE FILM

«(

FILM DIMENSIONS (Inches)
D
E
G
.079
<.001
.0730
.0730
.079
<.001
.079
.0780
<.001
.0780
.079
<.003
.0730
.079
<.001
.0780
.086
<.001

1
.999
.999
.999
.999
.999
1.049

L*
18.70
18.66
18.70
18.66
18.70
18.70

R

.020
.020
.013
0.13

' "Long Pitch" negative; J "Short Pitch" standard negative; 3 Standard positive
'This dimension represents the length of any 100 consecutive perforation intervals.

made in two basic shapes described
as being either negative or positive.
Negative perforations are designed
for pulling film through the camera. To
insure a steady image on the screen,
the perforations are shaped to en¬
gage the camera pull-down and regis¬
tration mechanism precisely so that
the frame will remain absolutely stea¬
dy during the interval of exposure.
Positive type perforations have a
shape intended to reduce the chance
of cracking with repeated use as a
film goes through a projector. "Nega¬
tive" or "Positive" perforations de¬
scribe the shape of the perforation
and not the type of film involved,
which may be either negative, posi¬
tive or reversal film. Background plates,
titles, mattes, dupes, etc., may use
either negative or positive perforations
to fit a particular need, regardless of
type of image.

Pitch
Both negative and positive 35mm
films are supplied in both short and
long pitch. Films intended for camera
use in original photography or special
effects (such as opticals) and subse¬
quent release printing are supplied
with negative perforation, short pitch
(1866). Negative perforation, long
pitch (1870), is supplied as a camera
original stock when release printing is
not anticipated (usually reversal color
films). Long pitch is also used in spe¬
cial applicaHons, such as cameras op¬
erating at a higher than normal frame
rate.
Positive
perforation,
long
pitch
(1870), is used primarily for printing
stock intended for direct projection,
frequently called "positive raw stock."
Positive perforation, short pitch (1866)
is also available for special purposes.
Identification

65/70mm FILM DIMENSIONS

E-

°1

T

K
1
£
o
^
o
o
o
O
1
-o
a
o
o
o
Gr

ft

r

"ft

o
*
:a

o
R ~X°-

-E

1
B
T

ASA STAND.

FILM
65mm, KS-1866
65mm, KS-1870
70mm, KS-1870

PH22.145
PH22.118
PH22.119

A
2.558
2.558
2.754

B
.1866
.1870
.1870

C
.1100
.1100
.1100

FILM DIMENSIONS (INCHES)
E
G
D
.0780
.177
.002
.0780
.002
.117
.0780
.215
.002

*This dimension represents the length of any 100 consecutive perforation intervals.

766

1

2.104
2.104
2.104

L*
18.66
18.70
18.70

R
.020
.020
.020

Perforations for 35mm are describ¬
ed by abbreviated terms "BH" (BellHowell) and "KS" (Kodak Standard)
indicating "negative" and "positive"
type perforations respectively. These
are followed by a number indicating
pitch (1866 or 1870) in decimal inch¬
es. For example, 35mm negative film
perforated for motion picture camera
use and intended for subsequent re¬
lease printing would be perforated to:
PH22.93-1964 (BH-1866). The first set
of numbers refers to the American
Standards Association description of a
negative type, short pitch perforation,
and the date on which it was adopted.
The second set indicates that this negContimied on Page 800

AMERICAN CINEMATOGRAPHER, OCTOBER 1968
American Cinematographer - October 1968

Table of Contents for the Digital Edition of American Cinematographer - October 1968
