Grey sky, mid-morning, mid-October. This is the light most people complain about and then shoot in anyway, because you don’t get to reschedule a trip around the forecast. It’s also the only light that renders a square like this one without tearing the exposure apart. Look at what the cloud cover is doing. The pale plaster on the west range keeps its texture. The arcades underneath aren’t black holes. The dark Gothic towers of the Týn Church hold detail instead of going to silhouette, which is exactly what happens to them against a clear blue sky at this hour.

Tamron has announced the 12-20mm F2.8 (Model A084), a fast ultra-wide zoom for Sony E-mount and Nikon Z full-frame mirrorless. The number that matters is the wide end: 12mm on a full-frame sensor is a 122-degree diagonal field of view, and holding F2.8 across the whole range puts this lens directly at astrophotography and cramped-interior work. What makes the announcement worth a second look is the packaging. At 119.3mm long and 570g on the Sony mount, this is not the usual full-frame ultra-wide brick.