The Rainbow (Evening of a Rainy Autumn Day), Willem Roelofs
On Google Art Project. High-res downloadable file on Wikimedia Commons. Originai is in the Gemeentemuseum, Den Haag.
It’s difficult to paint a rainbow without succumbing to the picturesque, but 19th century Dutch painter Willem Roelofs accomplishes it brilliantly — by pushing the prismatic phenomenon into the background and emphasizing the dramatic post-storm transition from shadow to sunlight.
Link: The Rainbow, Google Art Project