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.

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