Leica Summarit-S 70mm 2.5 ASPH CS User Manual

LEICA Summarit-S 70 mm ASPH. f/2.5

Technical Data.

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CS

Illustration 1:2

TECHNICAL DATA

Order no.

Image angle

(diagonal, horizontal, vertical)

Optical design

Number of lenses / groups 8 / 6

Entrance pupil infinity: 26.66 mm (in front of bayonet in incident light direction),

Focusing range 0,5 m to ∞

Distance setting

Scales Combined meter/feet graduation

Smallest object field 142 mm × 212 mm

Largest reproduction ratio 1 : 4,7

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. 93 / 151 mm (without / with lens hood)

Largest diameter approx. 90 / 117 mm (without / with lens hood)

Weight approx. 740 / 890 g (without / with central shutter)

11055 (CS: 11051)

approx. 42° / 35° / 24°, corresponds to approx. 56 mm focal length in 35 mm format

close focus limit: 43.62 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 70 mm ASPH. f/2.5

ENGINEERING DRAWING LENS SHAPE

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CS

ASPH.

Illustration 1:2

The Summarit-S 70 mm f/2.5 ASPH. plays the role of the standard lens in the Leica S-System lens-portfolio, and
has a focal length corresponding to 56 mm in 35 mm format. In order to ensure its universal versatility, the Leica
design engineers invested immense effort to guarantee superior image performance at maximum aperture and at
all focusing distances.

One of the eight lenses arranged in six groups features an aspherical surface, to minimise aberration effects.
The two cemented elements are manufactured from glass with high anomalous partial dispersion, minimising
the effect of chromatic aberrations. In addition, glasses with very high refractive indices work together with the
aspherical element to almost completely eliminate monochromatic aberration effects. In order to achieve perfect
image performance from infinity to its minimum focusing distance of just 50 cm (~1.6 ft), the last two lenses are
constructed as a floating element that moves independently from the rest of the optical system when focusing. The
Leica Summarit-S 70 mm f/2.5 ASPH. is ideally protected against water droplets and dust and features a protective
neutral glass filter that is included as a parameter in its optical design.

The reward for the immense effort invested in its design and construction is a lens with extraordinarily good
contrast performance wide open and at all other apertures that, even at its closest focusing distances, can be
only marginally improved in the extreme corners of images by stopping down. With a value of only 1.2 %, distortion
remains imperceptible, and maximum vignetting of 1.4 stops at maximum aperture is so extremely low, ensuring
that the Leica Summarit-S 70 mm f/2.5 ASPH. delivers consistently dependable and superior image performance at
all apertures and distances.

Floating Element

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