Canon has just launched what it claims is the "widest auto focus zoom lens ever made for a full frame camera", the RF 10-20mm F4L IS STM. It is a non-fisheye (aka rectilinear) lens which provides zero distortion with straight lines right to the frame edges, making it the ideal lens for architectural and landscape photography. The compact 570 g lens can be pre-ordered for US$2,299 and will be available in November.