LEICA ELMAR-M 24 mm f/3.8 ASPH. 1
The LEICA ELMAR-M 24mm f/3.8 ASPH. is an extremely compact lens, especially for such a wide angle, which also offers out- standing imaging performance. Even with at full stop, it delivers uniformly excellent reproduction quality over the entire image field, only deteriorating slightly towards the edges in the close-up range. This performance can only be improved slightly by stop- ping down, which means that you can take photographs with at full stop without concerns, unless your compositional ideas call for a greater depth of field that can only be achieved with smaller apertures. The vignetting characteristic of every optical system is naturally more pronounced on a super wide angle lens than on normal and long focal length lenses. With the diaphragm com- pletely open, it is a maximum - i.e. in the corners of the image - of around 1.9 stops for the 35mm format, or around 1.1 stops on Leica M8 models with their slightly smaller format. Stopping down to 5.6 visibly reduces this light falloff at the image edges - to 1.4 and 0.8 stops respectively. Stopping down further does not bring about any notable reduction since essentially only the natu- ral vignetting remains. The lens' maximum distortion is around 1% and therefore hardly perceptible.The retrofocus-like construc- tion is made up of a total of eight lens elements and the use of an aspherical surface and glass types with anomalous color dispersion (partial dispersion) make a crucial contribution towards restricting aberrations to an absolute minimum.
Summary: The LEICA ELMAR-M 24mm f/3.8 ASPH. not only offers optimum imaging performance but also - for its focal length - compact dimensions and also provides all Leica M users with an affordable introduction to the world of super wide angle photo- graphy.
ASPH. Lens shape LEICA ELMAR-M 24 mm f/3.8 ASPH. 2
Engineering drawing
Technical Data Angle of view (diagonal, horizontal, vertical) 84° / 74° / 53° Optical design Number of lenses/groups: 8 / 6 Focal length: 24.5 mm Position of entrance pupil: 18.7 mm (related to the first lens surface in light direction) Focusing range: 0.7 m to infinity Distance setting Scales: Combined meter/feet graduation Smallest object field: 615 x 922 mm Largest reproduction ratio: 1:25.6 Aperture Setting/Function: With click-stops, half values available, manual diaphragm Lowest value: 16 Bayonet Leica M quick-change bayonet with 6 bit lens identification bar code for digital M models Filter mount/Lens hood Non-rotating, female thread for filters E46, male thread for lens hood, screw-on type lens hood (included in delivery) Dimension and weight Length: 40.6 / 56.6 mm (without / with lens hood) Largest diamater: approx. 53 mm Weight: approx. 260 g 100 100
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100 5 4 80 3 LEICA ELMAR-M 24 mm f/3.8 ASPH. 2 3 60 1 0 40 -1 -2 20 -3 -4 0 -5 MTF graphs 05101520 05101520
Aperture Stop 3.8 Aperture Stop 8.0 [%] [%] 100 100 100
80 80 80 12 60 60 60 100 100 9 40 40 40 6 80 80
20 20 20 3 60 60 0 0 0 0 40 0 5 10 15 20 40 051015200 5 10 15 20 0369121518 Y' [mm] = 21.0 Y' [mm] = 21.0 20 20
100 5 0 0 051015204 05101520 80 3 2 Aperture Stop 5.6 60[%] 1 100 50 The MTF is indicated both at full aperture and at 4 f/5.6 at long taking distances (infinity). Shown 40 -1 is the contrast in percentage for 5, 10, 20 and 80 -23 40 lp/mm accross the height of the 35 mm film 20 -32 format, for tangential (dotted line) and sagittal 60 1 (solid line) structures, in white light. The 5 and -4 10 lp/mm will give an indication regarding the 0 -50 contrast ratio for large object structures.The 40 05101520-1 0510152020 and 40 lp/mm records the resolution of finer and finest object structures. -2 20 -3 -4 sagittal structures 100 ______tangential structures 0 -5 0 5 10 15 20 05101520 80 Y' [mm] = 21.0 12 60 100 9 40 6 80 12 20 3 60 9 0 0 40 05101520 0369121518 6
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100 100 100 5 4 80 80 80 3 LEICA ELMAR-M 24 mm f/3.8 ASPH.2 4 60 60 60 1 0 40 40 40 -1 -2 20 20 20 -3 -4 0 Distortion0 0 -5 05101520 0510152005101520 05101520
Relative Distortion Effective Distortion [%] 100 5 100 4 Y'[mm] 80 3 80 2 12 60 1 60 9 0 40 40 -1 6 -2 20 -3 20 3 -4 0 -5 0 0 05101520 0 5 0510152010 15 20 0 3 6 9 12 15 18 Y' [mm] = 21.0 X'[mm]
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40 Vignetting 6[%] 100 100 Distortion is the deviation of the real image height 20 3 (in the picture) from the ideal image height. The relative distortion is the percentage deviation. 80 80 8.0 5.6 The ideal image height results from the object 0 0 3.8 height and the magnification. The image height of 05101520 0369121518 60 60 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- 40 40 tes the appearance of straight horizontal and verti- cal lines in the picture.
20 20 Vignetting is a continous decrease of the illumina- tion to the edges of the image field. The graph 0 0 shows the percentage loss of illumination over the 05101520 0 5 10 15 20 image height. 100% means no vignetting. Y' [mm] = 21.0
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0 0 05101520 0369121518 LEICA ELMAR-M 24 mm f/3.8 ASPH. 5
Depth of field table
Aperture Stop Magnification 3,8 5,6 8 11 16 0,7 0,623 - 0,802 0,592 - 0,862 0,556 - 0,959 0,517 - 1,118 0,465 - 1,560 1/25,6 0,8 0,699 - 0,939 0,660 - 1,024 0,615 - 1,167 0,567 - 1,419 0,503 - 2,242 1/29,7 1 0,843 - 1,234 0,786 - 1,391 0,721 - 1,679 0,654 - 2,277 0,569 - 5,781 1/37,9 1,2 0,978 - 1,563 0,900 - 1,829 0,814 - 2,37 0,729 - 3,815 0,623 - ∞ 1/46 1,5 1,163 - 2,129 1,053 - 2,667 0,936 - 4,047 0,823 - 11,77 0,688 - ∞ 1/58,3 2 1,436 - 3,338 1,269 - 4,926 1,100 - 13,73 0,946 - ∞ 0,769 - ∞ 1/78,7 3 1,876 - 7,731 1,596 - 32,20 1,335 - ∞ 1,110 - ∞ 0,872 - ∞ Distance SettingDistance [m] 1/120 5 2,484 - ∞ 2,012 - ∞ 1,608 - ∞ 1,290 - ∞ 0,975 - ∞ 1/201 ∞ 4,838 - ∞ 3,298 - ∞ 2,324 - ∞ 1,704 - ∞ 1,188 - ∞ 1/∞
Aperture Stop 3,8
0,7 0,8 1 1,2 1,5 2 3
Distance[m]Setting 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
DistanceSetting[m] 5 ∞
0 1 2 3 4 5 6 7 8 9 10 Depth of Field [m] LEICA ELMAR-M 24 mm f/3.8 ASPH. 7
Aperture Stop 8
0,7 0,8 1 1,2 1,5 2 3
Distance[m]Setting 5 ∞
0 1 2 3 4 5 6 7 8 9 10 Depth of Field [m]
Aperture Stop 11
0,7 0,8 1 1,2 1,5 2 3
Distance[m]Setting 5 ∞
0 1 2 3 4 5 6 7 8 9 10 Depth of Field [m]
Aperture Stop 16
0,7 0,8 1 1,2 1,5 2 3
DistanceSetting[m] 5 ∞
0 1 2 3 4 5 6 7 8 9 10 Depth of Field [m]
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