See my Guide to Leica.
On the way for testing is the new Leica 21mm f/3.4 Super-Elmar-M ASPH, which looks to be the highest performing 21mm every offered by Leica for the M bodies.
In particular, I am excited about the claimed performance under difficult lighting conditions, as well as the high level of color aberration correction, all with very low distortion for a 21mm lens.
The new Super Elmar-M 21mm f/3.4 ASPH (about $2995) looks to fill a gap in the M line with another highly compact and very high performance wide angle, joining the 18mm f/3.8 Super-Elmar-M ASPH and the 24mm f/3.8 Elmar-M ASPH (both highly recommended).
Nominal, as per Leica.
|Angle of view
(diagonal, horizontal, vertical):
|for 35mm (24x36mm): 91°, 80°, 59° for M8 (18x27mm): 74°, 64°, 46° (Equivalent focal length : approx. 28mm)|
|Optical design:||Number of lenses/groups: 8 / 7 Aspherical surface: 2
|Position of entrance pupil:||Position of entrance pupil: 15,6mm (related to the first lens surface in light direction)|
|Focusing range:||0.7m to infinity|
|Distance setting Scales:||Combined meter/feet graduation|
|Largest reproduction ratio:||1:29.4
706 mm x 1059 mm (35mm) / 530 mm x 795 mm (for M8)
|Aperture:||With click-stops and half-stop clicks, f/3.4 to f/16|
|Bayonet:||Leica M quick-change bayonet with 6 bit lens identification bar code for digital M models|
|Filter mount:||female thread for screw-on filters size E46
Male thread with stop for lens hood (included in delivery)
|Dimensions:||43/55mm (with/without Lens hood), diameter 53 mm|
Performance according to the MTF charts looks to be near optimal wide open at f/3.4 for coarse structures (very impressive), improving only very slightly by stopping down to f/5.6 for fine structures and for contrast in corners. This is a very high performer, though the corners do drop off somewhat. It seems likely that color aberrations are also better corrected than with the 21mm f/1.4 Summilux-M ASPH.
Stopping down to f/8 actually degrades lens performance, and f/5.6 is only a small improvement over f/3.4: this is a very, very high performing lens.
The MTF charts also suggests a nearly flat field, and there is absolutely minimal astigmatism, both attributes that are admirable for digital (see Making Sharp Images).
Distortion (wave type from barrel to pincushion) looks to be very low for a 21mm lens, though not as low as the slower Zeiss ZM 21mm f/4.5 Biogon (which unfortunately has color shading issues on the M9 due to extreme ray angles).
Leica’s description of the 21mm f/3.4 Super-Elmar-M ASPH:
With the LEICA SUPER-ELMAR 21 mm f/3.4 ASPH., Leica is extending the range of M lenses in the super wide angle range with a model that combines outstanding reproduction with a compact design. It delivers uniformly excellent reproduction quality over the entire field of view, with only a very slight deterioration at the edges in the close-up range.
This performance can only be improved slightly by stopping down, which means that you can take photo- graphs with full stop with no concerns, unless your compositional ideas call for a greater extension of the depth of field that can only be achieved with smaller apertures.
The vignetting characteristic of every optical system is more pronounced on a super wide-angle lens than on normal lenses and those with long focal lengths. At full stop in 35mm format it is a maximum, i.e. in the corners of the image, of around 2,1 stops, around 1,2 stops on Leica M8 models with their slightly smaller format. Stopping down to f/5.6 reduces this light falloff at the edge of the image – to 1.6 and 1.0 stops respectively. Stopping down further does not result in any further reduction as essentially only the natural vignetting remains.
The maximum distortion of the lens of around 1.5 % is hardly perceptible.
The retrofocus-like construction is made up of a total of eight lens elements, and the use of a lens element with two aspherical surfaces and four lens elements made of glass types with anomalous color dispersion (partial dispersion) make a crucial contribution towards restricting aberrations to an absolute minimum.
Summary: The LEICA SUPER-ELMAR-M 21 mm f/3.4 ASPH. combines optimum reproduction with compact dimensions, offering all M users a wide range of options in the spontaneous super wide-angle photography that is typical of the Leica M.
Leica press release
Note that “available July” has actually meant available right about now (November).
NEW: THE LEICA SUPER-ELMAR-M 21MM F/3.4 ASPH.
Compact M lens with improved imaging performance sets new standards in wide-angle photography
Solms, Germany (June 21, 2011) - Leica Camera AG adds a new, high-performance wide-angle lens to its portfolio of short focal length lenses for Leica M cameras. The Leica Super-Elmar-M 21 mm f/3.4 ASPH. sets new standards in imaging performance. It is characterized by its particularly compact size and suitability for a wide range of photographic situations. Whether used for photojournalism, architecture or landscape photography, the Leica Super-Elmar-M 21 mm f/3.4 ASPH. provides photographers with an extremely small, light and versatile wide-angle lens, particularly suitable for travelling.
The performance of the Leica Super-Elmar-M 21 mm f/3.4 ASPH. is reminiscent of one of the all-time favorite classic M lenses, the Leica Super-Angulon-M 21 mm f/3.4. This highly praised lens was an integral part of the Leica M lens portfolio from 1963 to 1980 and made its name and reputation as an ideal tool for available light photography and photojournalism. Even today, the Super-Angulon-M 21 mm f/3.4 remains extremely popular and one of the most sought-after M lenses amongst connoisseurs of fine optics.
The new Leica Super-Elmar-M 21 mm f/3.4 ASPH. is a worthy successor, with further improvements over the already outstanding performance of its forerunner model. The lens reveals its excellent reproduction of detail and superior contrast at maximum aperture. Of particular note is the extremely effective optimization of flare characteristics of the Leica Super-Elmar-M 21 mm f/3.4 ASPH., which allows the capture of fascinating ‘contre-jour’ images with absolute clarity and contrast.
The intricate optical design and construction of the lens are responsible for its outstanding sharpness and imaging qualities. The Leica Super-Elmar-M 21 mm f/3.4 ASPH. is constructed with eight lenses in seven groups. At the same time, the use of one lens element with two aspherical surfaces and four lenses with anomalous partial dispersion ensure that aberrations are reduced to an absolute minimum.
As with all Leica lenses, the Super-Elmar-M 21 mm f/3.4 ASPH. was designed and developed by Leica specialists in Solms, Germany and represents the perfect combination of optical and technical expertise. Particularly reliable and with enduring value, every Leica lens is manufactured from only the highest quality materials and is assembled with meticulous precision, completely by hand. The combination of cutting-edge technologies and extremely thorough manufacturing processes guarantees consistently excellent quality.
The Leica Super-Elmar-M 21 mm f/3.4 ASPH. is supplied with a high-quality, all-metal lens hood, which should be mounted at all times. The hood not only protects the lens effectively against reduction of contrast by extraneous light, but also against damage and the accumulation of dirt on the front lens element.
The Leica Super-Elmar-M 21mm f/3.4 ASPH. will be available from Leica dealers beginning July 2011.