Item
|
Designation
|
NF S 27001 standard
|
Protocol 89/97
(exceptional cases)
|
Recommended value
|
C.1.1
|
Screen to front-row distance
|
0.6 Cinemascope width
|
0.5 Screen width
|
0.8 Screen width
|
C.1.1
|
Screen to last-row distance
|
2.9 Cinemascope width
|
2.9 Screen width
|
2 Cinemascope width
|
C.1.2
|
Front-row head tilt angle/ top of the screen
|
45° (eye at 1.00 m/ floor)
|
45° (eye at 1.10 m/ floor)
|
40°
|
C.1.2
|
Front-row head tilt angle/ screens centre
|
30° (eye at 1.00 m/ floor)
|
30° (eye at 1.10 m/ floor)
|
30°
|
C.1.3
|
Row spacing on even
floor (m)
|
0.80
|
0.80
|
0.90
|
C.1.3
|
Row spacing on tiered floor (m)
|
0.90
|
0.90
|
1.00
|
C.1.4
|
Side vision angle (degrees)
|
20
|
20
|
16
|
C.1.5
|
Seat back plane/screen plane (degrees)
|
20
|
20
|
See complete guide
|
C.1.6
|
Head clearance (m)
|
0.12
|
0.12
(0.09 on first Protocol)
|
0.15
|
C.1.7
|
Upper plane (degrees)
|
20
|
20
|
20
|
C.2.1
|
Screen curvature radius
|
R 2 D (screen/last row)
|
R 1.5 D (screen/last row)
|
R 2 D (screen/last row)
|
C.2.2
|
Vertical geometrical image distortion (%)
|
3 (tolerance 5)
|
3 (tolerance 5)
|
3
|
C.2.3
|
Horizontal geometrical image distortion (%)
|
3 (tolerance 5)
|
3 (tolerance 5)
with ratio
Projection distance/screen height > 3.5
|
3 (tolerance 5)
with ratio
Projection distance/screen height > 4
|
C.2.4
|
Clearance under projection beam (m)
|
2.00
(tolerance 1.80 on front half for rooms < 200 places)
|
2.00 above aisles
1.80 above seats
|
2.00
|
|
Background noise level
|
|
|
NC 27 (digital)
NC 30 (analogue)
|