Here is just one quick example of Andre Kertesz’ work with shadow – which repays close observation.
It reminds me of David Hockney – here in Portrait of an artist (Pool with 2 figures) painted by David Hockney (below)
Hockney was so absorbed with the reflections within water that he painted the bottom of his pool with physical blue curves, to give that sense of movement:
Comma And 
Reblogged this on Comma And and commented:
A little bit more about David Hockney, as it’s his 80th birthday – a repost from February