CamPerform CP80-3-M/C-540
Ref. 1888-SU-01-C
Page 27
A: Distance from lens to object in mm
B: Object size in mm
C: Number of horizontal pixels
D: Number of vertical pixels
Example:
C: Number of horizontal pixels = 1200
D: Number of vertical pixels = 1200
A: Distance from lens to object = 300 mm
B: Object size = 100 mm
calculated focal length = (300 : (1 + (100 : 13,6))) = 36 mm
when a lens with focal length of 35 mm has to be used, and the object size has
to be kept at 100 mm, the distance from lens to object has to be changed as
follows:
at a focal length of 35mm, an object size of 100mm and a sensor size of
15,4mm the new distance from lens to object is calculated as:
35
⋅
(1 + (100 : 13,6)) = 292 mm
The distance from lens to object has to be reduced from 300mm to 292mm.
Vice versa, when the distance from lens to object has to be reduced, the focus
of the lens will come to its limit. and the required magnification factor can no
more performed by the lens itself. In this case, a distance washer has to be
placed between the lens interface of the camera and the lens.
]
[
1
]
[
mm
Size
Sensor
B
A
mm
Length
Focal
+
=
6
,
13
1200
1200
008
,
0
]
[
2
2
=
+
⋅
=
mm
Size
Sensor
+
⋅
=
Size
Sensor
Size
Object
Length
Focal
mm
Object
to
Distance
1
]
[
