Leica 11645 Camera Lens User Manual


 
LEICA SUMMARIT-M 75 mm f/2.5
4
Distortion
Vignetting
0 5 10 15 20
Y' [mm] = 21.0000
-5
-4
-3
-2
-1
0
1
2
3
4
5
[%]
Relative Distortion
0 5 10 15 20
0
20
40
60
80
100
[%]
Vignetting
2.5
4.0
5.6
0 3 6 9 12 15 18
X'[mm]
0
3
6
9
12
Y'[mm]
Effective Distortion
Distortion is the deviation of the real image height
(in the picture) from the ideal image height. The
relative distortion is the percentage deviation.
The ideal image height results from the object
height and the magnification. The image height of
21.6mm is the radial distance between the edge and
the middle of the image field for the format 24mm x
36mm. The graph of the effective distortion illustra-
tes the appearance of straight horizontal and verti-
cal lines in the picture.
Vignetting is a continous decrease of the illumina-
tion to the edges of the image field. The graph
shows the percentage loss of illumination over the
image height. 100% means no vignetting.