Sigma Unveils the First Constant f/1.8 Zoom Lens
The real-life focal range may translate to 27mm to 52.5mm with 35mm equivalent, if we figure out the crop factor. This should make the lens adequate for street photography, close-up, studio, wedding, portraits and landscapes.
It has 72mm filter size and an f/1.6 minimum aperture. The lens should produce really sweet bokeh, thanks to the nine-blade rounded diaphragm. It should perform quite well at extreme temperatures with TSC (thermally stable composite) compound material and AF/MF switch.