Sigma 18mm F2.8
Launched February 1980

Sigma 18mm F2.8 Ultra wide angle Lens

(This press release text is from 1980; the lens may be related to the XQ Filtermatic of 1977).

Compact and lightweight rectilinear ultra wideangle lens with a fast lens speed of F2.8 Based on a new optical design, only the front 7 groups of elements are moved while focusing to achieve a better compensation for various aberrations.

Specifications
Construction	11 Elements in 9 Groups
Focal Length	18mm
Maximum Aperture	ƒ2.8
Minimum Aperture	ƒ22
Field of View	100°
Minimum Focus Distance	25cm
Number of blades	N/A
Maximum Magnification	N/A
Zooming System	N/A
Filter Size	67mm
Diameter	74mm (max.)
Length	70.5mm
Weight	325g
SRP at launch:	N/A
Available Mounts:	N/A