|
 |
|
|
|
|
ATTAINING THE REQUIRED LENS IN MILLIMETERS
(without using a Field of View Calculator) |
|
|
|
|
|
|
|
H = Horizontal area (in feet)
V = Vertical area (in feet)
OD = Object Distance from lens and
viewing area (in feet)
F = Required Focal Length (in
millimeters)
|
|
| 1/3" |
1/2" |
2/3" |
|
F = 4.8 X OD
H |
F = 6.4 X OD
H |
F = 8.8 X OD
H |
|
F = 3.6 X OD
V |
F = 4.8 X OD
V |
F = 6.6 X OD
V |
|
H = 4.8 X OD
F |
H = 6.4 X OD
F |
H = 8.8 X OD
F |
|
V = 3.6 X OD
F |
V = 4.8 X OD
F |
V = 6.6 X OD
F |
|
Example: Using a 1/3" camera, you want to see a 12 foot horizontal field of view
from 25 feet away.
4.8
X 25 = 120 = 10 mm lens (1/3"
format)
12
12
|
|
|
|
