Leica Summarit-S 35mm 2.5 ASPH User Manual

LEICA Summarit-S 35 mm f/2.5 ASPH.

Technical Data.

/

CS

Illustration 1:2

TECHNICAL DATA

Order no.

Image angle

(diagonal, horizontal, vertical)

Optical design

Number of lenses/groups 11 / 9

Entrance pupil infinity: 84.77 mm (in front of bayonet in incident light direction),

Focusing range 0,55 m to ∞

Distance setting

Scales Combined meter/feet graduation

Smallest object field 334 mm × 502 mm

Largest reproduction ratio 1 : 11,1

Aperture

Setting / Function Electronically controlled diaphragm, set using setting/

Lowest value 22

Bayonet

Filter mount / Lens hood

Dimensions and weight

Length to bayonet mount approx. 122 / 156 mm (without / with lens hood)

Largest diameter approx. 88 / 132 mm (without / with lens hood)

Weight approx. 930 / 1080 g (without / with central shutter)

11064 (CS: 11050)

approx. 74° / 64° / 45°, corresponds to approx. 28 mm focal length in 35 mm format

close focus limit: 84.85 mm (in front of bayonet in incident light direction)

selection dial on camera, including half values

Leica S bayonet

External bayonet for lens hood (included), internal thread for
E72 filter, filter mount does not rotate

Leica Camera AG / Oskar-Barnack-Strasse 11 / 35606 SOL MS / GERMANY / Phone [phone] I Fax [phone] / www.leica- camera.com

Page 1 of 6 / As at September 2012 / Speci fications are subject to change without notice

LEICA Summarit-S 35 mm f/2.5 ASPH.

ENGINEERING DRAWING LENS SHAPE

/

CS

ASPH.

ASPH.

Illustration 1:2

With an angle of view corresponding to that of a 28 mm lens in 35 mm format, the Leica Summarit-S 35 mm f/2.5
ASPH. can be used as a universal wide-angle lens with characteristically dramatic perspectives. At the same time,
its unusually fast initial aperture offers fascinating creative potential for the use of selective focusing to isolate
subjects from their surroundings. The alternative CS version with a central shutter and a close focusing limit of only
55 cm (~1.8 ft), offers extreme versatility for a wide range of photographic needs.

The combination of a fast initial aperture and a wide angle of view are only possible by the investment of enormous
effort in the design and construction of such a lens. And here, Leica employs the benefits of numerous years of
experience gained in the production of lenses with aspherical surfaces, a feature very rarely found in such large­diameter lenses. In the front group, a lens with an aspherical surface created in an immensely precise grinding and
polishing process guarantees extremely low distortion, and a further aspherical surface is employed in the rear
groups. Altogether, five of the eleven lenses arranged in nine groups are manufactured from glass with anomalous
partial dispersion, and three are fluoride lenses with particularly low dispersion (colour scattering) characteristics.
Rear group focusing in this splash-proof and dust sealed lens ensures consistent imaging performance from infinity
to the closest focusing distances and a constant length when focusing.

Thanks to this special construction, the image performance of the Summarit-S 35 mm f/2.5 ASPH., is exceptionally
good wide open and can be improved only very slightly in the corners of images by stopping down. A vignetting
value of just 1.4 stops, and distortion no greater than 1.7 %, even at its closest focusing limit, are imperceptible in
practical use. The outcome of the enormous effort invested in the design and construction of this lens is a wide­angle lens that allows photographers to fully exploit its creative opportunities without compromise.

Leica Camera AG / Oskar-Barnack-Strasse 11 / 35606 SOL MS / GERMANY / Phone [phone] I Fax [phone] / www.leica- camera.com

Page 2 of 6 / As at September 2012 / Speci fications are subject to change without notice