22
Projection Distance and Size
Use the figures, tables, and formulas below to determine the projection size and projection
distance. (Projection sizes are approximate values for full-size picture with no keystone
adjustment.)
Screen
As seen from above
As seen from the side
a
is the distance (cm, feet) between the lens and the screen, and corresponds to a range of
1 m to 11.88m (3.28 ft. to 38.97 ft.).
H
is the height (cm, feet) from the image bottom to the
center of the lens.
90
a
90
H
Lens center
projection
size
(inches)
Wide
Tele
Offset
distance
distance
height (H)
(m)
(feet)
(m)
(feet)
(cm)
(feet)
23.9
---
---
1.00
3.28
5.5
0.18
30
1.15
3.77
1.28
4.19
6.9
0.23
40
1.56
5.10
1.73
5.66
9.1
0.30
60
2.37
7.77
2.62
8.60
13.7
0.45
80
3.18
10.43
3.52
11.53
18.3
0.60
100
3.98
13.07
4.41
14.46
22.9
0.75
150
5.99
19.64
6.62
21.72
34.3
1.13
200
7.97
26.15
8.82
28.93
45.7
1.50
250
9.93
32.59
10.99
36.07
57.2
1.88
300
11.88
38.97
---
---
68.6
2.25
Placement (Continued)
min length
a(cm)= -0.000381 x projection size (inches)
2
+ 4.1 x projection size (inches) - 7.8
a(feet)= -0.0000125 x projection size (inches)
2
+ 0.135 x projection size (inches) - 0.256
max length
a(cm)= -0.000365 x projection size (inches)
2
+ 4.52 x projection size (inches) - 7.7
a(feet)= -0.000012 x projection size (inches)
2
+ 0.148 x projection size (inches) - 0.253
height
H(cm)= projection size (inches) x 0.2286
H(feet)= projection size (inches) x 0.0075
