Formula for calculation

It is important to know the angle of view of the lens to take in the object.? Angle of view changes with focal length of lens and image size of camera.? The focal length to cover the object can be calculated from the next formula.

f : focal length of lens
V: Vertical size of object
H: Horizontal size of object
D: Distance from lens to object
v : vertical size of image (see the following table)
h : horizontal size of image (See the following table)

Format	1 inch	2/3 inch	1/2 inch	1/3 inch
v	9.6mm	6.6mm	4.8mm	3.6mm
h	12.8mm	8.8mm	6.4mm	4.8mm

Examples

a) In case of vertical size

1/2 inch camera
Vertical size of object
Distance from lens to object

substitute these data to formula (1)

v=4.8mm V=330mm D=2500mm

b) In case of horizontal size

1/2 inch camera
Horizontal size of object
Distance from lens to object

substitute these data to formula (2)

h=6.4mm H=440mm D=2500mm