If you drag the image around, you notice that the water has different highlight points at different angles. If you would stand in front of this painting, your natural body movement (of even a tree before the window) would constantly change the lighting and almost certainly result in a very natural-looking water surface. I cannot imagine reproducing this digitally without it feeling "artificial" or "forced".
https://artmyn.com/partners/sothebys-newyork/Michele_Mariesc...
If you drag the image around, you notice that the water has different highlight points at different angles. If you would stand in front of this painting, your natural body movement (of even a tree before the window) would constantly change the lighting and almost certainly result in a very natural-looking water surface. I cannot imagine reproducing this digitally without it feeling "artificial" or "forced".