I just googled him Brian; very talented, and yes the details are astonishing.
Just look at the color palette of his skies, the shape of his clouds, the perspective of the buildings and bridges, etc., the people postures, the realism in their day-to-day activities, ...everything is so minutia detailed and intricate. His vision was realistic and his painting style reflects just that; excellence of observation.
It must have taken him a long time to make one tableau/canvas (painting), and a large one at that.
By the way, by the time you replied to my post I was already at the link above, and looking at his paintings, plus more on himself, the master Canaletto.