Do Painters Need Vision?

Edgar Degas, c.1905. Pastel on paper, 28-1/8 x 24-3/4 in. Norton Simon Art Foundation. 

Most painters with long careers go through some critical changes in their exploration of the medium. Phillip Guston, Pablo Picasso and Edgar Degas are some of the painters I have seen change most radically. When I think of Degas, for example, I think of how most works are delicate and precise in theme and formal nature. While at the Norton Simon Museum, however, I came across Degas’ Woman Drying her Hair. Degas, once again, depicted a delicate scene of a woman. However, formally, the drawing differed from the rest of the large amount of Degas being displayed there. On Woman Drying her Hair, the lines were reckless, aggressive, nervous and fast—like small cuts—while on the other Degas’ drawings, the lines were placed methodically as a vehicle to illustrate a specific feature or object. 

While painters like Guston or Picasso seemed to have changed aesthetic intentionally, what happens when a change in aesthetic is triggered by a physical difficulty—where the artist's intention was not to change the aesthetic? This seems to be what happened to Degas, whose vision problems altered how he saw his own work. 

Michael Marmor, MD, wanted to know what it was like to see through the eyes of an artist. Literally. Marmor blurred the image in “Woman Drying Her Hair” to a visual acuity of 20/300 to replicate what Degas might have seen. Credit: Michael Marmor

A great article on Michael Marmor's research on how eye diseases have change the way painters see their work:
http://med.stanford.edu/news_releases/2007/april/art.html

I highly recommend to zoom in into the work and listen to the audio tour: 
http://www.nortonsimon.org/collections/browse_title.php?id=M.1969.06.P