I don't know about Canaletto, but I went to a gallery in Paris that was selling a Breughel collection, a roomful of them, and the Breughel the Younger pieces definitely rewarded viewing with the loupe which they courteously provided.
Edmund
Like I said they could paint to any level they thought it needed, Breugel painted detail where he thought he needed to. But that isnt what makes a Breugel compelling. Chances are he has used light and atmosphere to capture a past Flemish scene. The point is the difference between 30mp and 100mp isnt going to be what makes an image good or bad, the constant search for more blades of grass in an image is only something photographers bother about, society will not pick an image on detail no more than they give a dogs dangler about Bokeh. There is a much greater list before you get down to splitting hairs on less important details. More pixels sharper lenses is an easy fix for a photographer that thinks they can make what they have better and its an easy idea to sell.
I think the largest selling picture recently has been a couple doing the Tango on the beach with the butler holding an umbrella, very little detail but lots of atmosphere.
Cheers,
Kev