To prepare for the paintings, Canaletto used to experiment and prepare sketches of images of different elements that could be used for the final work.
Nothing different than most of other painters had always done, of course.
Interesting, though, is the fact that what can be found of these experimental drawings, depicts situations we will never see completed in finished drawings or paintings, and probably served as a reservoir where he could experiment and then use or reuse according to his needs.
Or just a testing for the right tecnique to display a person, a situation, a scrapbook of usable ideas.
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