LEICA SUPER-ELMAR-M 18 mm f/3.8 ASPH.
1
The LEICA SUPER-ELMAR-M 18 mm f/3.8 ASPH. features a lens element with two aspherical surfaces, ensuring outstanding opti-
cal performance across the image plane and at all f-stops. With the lens set to maximum aperture and mounted on a traditional
Leica M or digital LEICA M8 model, vignetting – an effect which is inherently more prevalent with super wide angle lenses –
amounts to a nominal 2.3 stops or 1.7 stops on an M8. Stopping down to f/5.6 reduces the vignetting to a value of 1.3 or 1
respectively. Maximum distortion, in turn, measures only 1.8 percent and is virtually undetectable to the human eye.
Summary: The LEICA ELMAR-M 18mm f/3.8 ASPH. not only offers optimum image performance, it has compact dimensions - for
its focal length - and provides all Leica M users with an economical introduction to super wide-angle photography.
Lens shape
ASPH.
LEICA SUPER-ELMAR-M 18 mm f/3.8 ASPH.
3
MTF graphs
Aperture Stop 3.8
Aperture Stop 8.0
[%]
[%]
100
80
60
40
20
0
100
80
60
40
20
0
0
5
10
15
20
0
5
10
15
20
Y' [mm] = 21.0
Y' [mm] = 21.0
Aperture Stop 5.6
[%]
100
80
60
40
20
0
The MTF is indicated both at full aperture and at
f/5.6 at long taking distances (infinity). Shown
is the contrast in percentage for 5, 10, 20 and
40 lp/mm accross the height of the 35 mm film
format, for tangential (dotted line) and sagittal
(solid line) structures, in white light. The 5 and
10 lp/mm will give an indication regarding the
contrast ratio for large object structures.The
20 and 40 lp/mm records the resolution of finer
and finest object structures.
sagittal structures
_ _ _ _ _ _ _ _
tangential structures
0
5
10
15
20
Y' [mm] = 21.0
LEICA SUPER-ELMAR-M 18 mm f/3.8 ASPH.
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Distortion
Effective Distortion
Relative Distortion
[%]
5
4
Y'[mm]
3
12
9
2
1
0
-1
-2
-3
-4
-5
6
3
0
0
3
6
9
12 15 18
X'[mm]
0
5
10
15
20
Y' [mm] = 21.0
Vignetting
[%]
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.
100
8.0
5.6
3.8
80
60
40
20
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.
0
0
5
10
15
Y' [mm] = 21.0
20
LEICA SUPER-ELMAR-M 18 mm f/3.8 ASPH.
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Depth of field table
Aperture Stop
Magnification
3,8
5,6
8
11
16
0,7
0,8
1
0,575 - 0,904
0,638 - 1,087
0,754 - 1,516
0,857 - 2,058
0,993 - 3,204
1,181 - 7,235
1,455 - ∞
0,532 - 1,054
0,584 - 1,317
0,677 - 2,026
0,758 - 3,160
0,860 - 7,187
0,994 - ∞
0,484 - 1,361
0,526 - 1,851
0,598 - 3,741
0,658 - 11,73
0,732 - ∞
0,436 - 2,178
0,469 - 3,879
0,523 - ∞
0,568 - ∞
0,620 - ∞
0,682 - ∞
0,759 - ∞
0,834 - ∞
0,979 - ∞
0,377 - ∞
0,399 - ∞
0,436 - ∞
0,465 - ∞
0,498 - ∞
0,535 - ∞
0,579 - ∞
0,619 - ∞
0,691 - ∞
1/34,5
1/39,9
1/50,9
1/61,8
1/78,2
1/106
1/160
1/270
1/∞
1,2
1,5
2
0,824 - ∞
3
1,177 - ∞
0,943 - ∞
5
1,788 - ∞
1,381 - ∞
1,065 - ∞
∞
2,721 - ∞
1,866 - ∞
1,324 - ∞
Aperture Stop 3,8
0,7
0,8
1
1,2
1,5
2
3
5
∞
0
1
2
3
4
5
6
7
8
9
10
Depth of Field [m]
Aperture Stop 5,6
0,7
0,8
1
1,2
1,5
2
3
5
∞
0
1
2
3
4
5
6
7
8
9
10
Depth of Field [m]
LEICA SUPER-ELMAR-M 18 mm f/3.8 ASPH.
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Aperture Stop 8
0,7
0,8
1
1,2
1,5
2
3
5
∞
0
0
0
1
1
1
2
2
2
3
3
3
4
5
6
6
6
7
7
7
8
8
8
9
9
9
10
10
10
Depth of Field [m]
Aperture Stop 11
0,7
0,8
1
1,2
1,5
2
3
5
∞
4
5
Depth of Field [m]
Aperture Stop 16
0,7
0,8
1
1,2
1,5
2
3
5
∞
4
5
Depth of Field [m]
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