Sigma 24mm f/1.8 EX DG lens

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Key features
Sigma 24mm f/1.8 EX DG
Maker:	Sigma Corporation
Image stabilization:	none
Ultrasonic motor:	n/a
Short back focus:	n/a
Macro capable:	Yes
Unique features:	Very fast maximum aperture
Application:	low-light, landscape, macro, general purpose wide angle
Technical data
Type:	wide angle lens
Focal length:	24 mm
Frame coverage:	84 degrees (FX or 35mm), 62 degrees ( DX or APS-C)
Aperture (max/min):	f/1.8, f/22
Construction:	9 groups / 10 elements
Close focus distance:	18 cm
Max. magnification:	1:2.7
Physical
Max. diameter:	84 mm
Max. length:	82 mm
Weight:	485 g
Filter diameter:	77mm
Accessories
Lens hood:	included (bayonet)
Case:	included (soft)
Angle of view
Horizontal:	73 degrees (FX or 35mm)/54 degrees (DX or APS-C)
Vertical:	54 degrees (FX or 35mm)/37 degrees (DX or APS-C)
Diagonal:	84 degrees (FX or 35mm)/62 degrees (DX or APS-C)
History
Retail info
MSRP US$	$450 (street price $340)

This large-aperture super-wide-angle lens features a fast f/1.8 maximum aperture for use in low-light situations, and macro focusing capability to a reproduction ratio of 1:2.7. The use of aspherical lens elements promises superior peripheral brightness and compensation of aberrations and astigmatism. Though intended for 35mm film and full-frame digital SLRs, this lens is available for several makes of APS-C digital SLR cameras, where the angle of view is similar to a moderate wide-angle lens (in the 35mm-40mm range, depending on the size of the D-SLR sensor).

This lens is capable of macro photography, with minimum focusing down to 18cm/7.1" (reproduction ratio 1:2.7). It incorporates a floating focus system in order to minimize distortion, spherical aberration and astigmatism, and provides high performance at all shooting distances. The high reproduction ratio and wide angle of view allow capturing high quality images not only of a subject but also the surrounding scenery.