With the announcement of the Tamron 20mm F/2.8 Di III OSD M1:2 (Model F050) prime lens for the Sony E-mount (RRP $599) there are now three wide-angle prime lenses from the specialist Japanese lens manufacturer, the others being 24mm and 35mm f2.8s.
The new lens focusses down to just 11cm for a maximum magnification of 1:2. It weighs 220g and is a fixed 64mm long, with internal focussing. It has moisture resistant construction and a dirt-resistant flourine coating.
‘If you can own only one ultra wide-angle, it should be your first choice,’ the Tamron press release advises.
Tamron 20MM f2.8 Sony E-Mount. Jan 2020