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|
|Field of View||100°|
|Minimum Focus Distance||25cm|
|Number of blades||N/A|
|SRP at launch:||N/A|