Leica Summicron-M 28mm f/2 ASPH User manual

LEICA SUMMICRON-M 28 mm f/2 ASPH. 1
This fast wide-angle lens is especially compact and its imaging performance is outstanding at f/2. The rendition of the finest details
results in pictures with an extraordinary depth effect. Even in critical lighting conditions, for example in backlit situations, distrac-
ting reflections and flare are largely eliminated. Because of its large aperture of f/2, it can also be used for selective sharpness set-
tings in the wide-angle range. And when pictures are to be taken without flash under unfavorable light conditions at twilight or in
sparsely illuminated rooms, this lens is highly recommended.
Lens shape
Asphere

LEICA SUMMICRON-M 28 mm f/2 ASPH. 2
Engineering drawing
Technical Data
Angle of view (diagonal, horizontal, vertical)
Optical design
Distance setting
Diaphragm
Bayonet
Filter (type)
Lens hood
Dimensions and weight
75°, 65°, 46°
Number of elements / groups: 9 / 6
Focal length: 28.5 mm
Entrance pupil: 12.8 mm (related to the first lens surface in light direction)
Focusing range: 0.7 m to Infinity
Scale: combined meter/feet-increments
Smallest object field: 528 mm x 793 mm
Highest reproduction ratio: 1:22
Setting / Type: with clickstops (including half values), manual diaphragm
Smallest aperture: f/16
Leica M quick-change bayonet
internal thread for screw-in type filters E 46
separate, clip-on type, lockable
Length: 40.8 mm
Largest diameter: 53 mm
Weight: approx. 270 g

LEICA SUMMICRON-M 28 mm f/2 ASPH. 3
0 5 10 15 20
Y’ [mm]
0
20
40
60
80
100
[%] Aperture Stop 2.0
0 5 10 15 20
Y’ [mm]
0
20
40
60
80
100
[%] Aperture Stop 5.6
0 5 10 15 20
Y’ [mm]
0
20
40
60
80
100
[%] Aperture Stop 2.8
MTF graphs
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.
tangential structures
sagittal structures
_ _ _ _ _ _ _ _

LEICA SUMMICRON-M 28 mm f/2 ASPH. 4
Distortion
Vignetting
0 5 10 15 20
Y’ [mm]
-5
-4
-3
-2
-1
0
1
2
3
4
5
[%]
Relative Distortion
0 5 10 15 20
Y’ [mm]
0
20
40
60
80
100
[%]
2.0
2.8
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 lost of illumination over the
image height. 100% means no vignetting.
tangential structures
sagittal structures
_ _ _ _ _ _ _ _

LEICA SUMMICRON-M 28 mm f/2 ASPH. 5
Depth of field table
Magnification
0,7 0,656 - 0,752 0,638 - 0,776 0,617 - 0,812 0,587 - 0,873 0,555 - 0,964 0,508 - 1,170 1/21,9
0,8 0,741 - 0,870 0,719 - 0,903 0,691 - 0,953 0,654 - 1,040 0,613 - 1,175 0,556 - 1,506 1/25,4
1 0,908 - 1,115 0,873 - 1,173 0,832 - 1,261 0,777 - 1,422 0,718 - 1,696 0,639 - 2,520 1/32,4
1,2 1,067 - 1,373 1,019 - 1,463 0,962 - 1,606 0,888 - 1,883 0,811 - 2,408 0,709 - 4,569 1/39,5
1,5 1,295 - 1,786 1,224 - 1,946 1,141 - 2,211 1,037 - 2,787 0,931 - 4,153 0,798 - 24,52 1/50,0
2 1,646 - 2,555 1,532 - 2,903 1,402 - 3,550 1,245 - 5,360 1,093 - 15,06 0,912 - ∞1/67,5
3 2,259 - 4,489 2,045 - 5,711 1,816 - 9,002 1,557 - 69,95 1,324 - ∞1,063 - ∞1/103
5 3,217 - 11,38 2,795 - 25,30 2,380 - ∞1,949 - ∞1,593 - ∞1,225 - ∞1/173
10 4,717 - ∞3,854 - ∞3,101 - ∞2,402 - ∞1,879 - ∞1,384 - ∞1/348
∞8,839 - ∞6,207 - ∞4,448 - ∞3,130 - ∞2,290 - ∞1,591 - ∞1/∞
Aperture Stop
811162,8 4 5,6
Distance Setting [m]
Aperture Stop 2,8
012345678910
∞
10
5
3
2
1,5
1,2
1
0,8
0,7
Distance Setting [m]
Depth of Field [m]
Aperture Stop 4
012345678910
∞
10
5
3
2
1,5
1,2
1
0,8
0,7
Distance Setting [m]
Depth of Field [m]

LEICA SUMMICRON-M 28 mm f/2 ASPH. 6
Aperture Stop 11
012345678910
∞
10
5
3
2
1,5
1,2
1
0,8
0,7
Distance Setting [m]
Depth of Field [m]
Aperture Stop 5,6
012345678910
∞
10
5
3
2
1,5
1,2
1
0,8
0,7
Distance Setting [m]
Depth of Field [m]
Aperture Stop 8
012345678910
∞
10
5
3
2
1,5
1,2
1
0,8
0,7
Distance Setting [m]
Depth of Field [m]

LEICA SUMMICRON-M 28 mm f/2 ASPH. 7
Leica Camera AG / Oskar-Barnack-Straße 11 / D-35606 Solms / Telefon + 49 (0) 6442-208-0 / Telefax + 49 (0) 6442-208-333
www.leica-camera.com / [e-mail]
Aperture Stop 16
012345678910
∞
10
5
3
2
1,5
1,2
1
0,8
0,7
Distance Setting [m]
Depth of Field [m]