It's a little bit of a Rackstraw Downes extravaganza right now, but well deserved. His plein air paintings are long term engagements with observation. Here are links to a couple of interviews that delve into his thinking about painting as well as paintings/painters that have influenced his work.
Jennifer Samet interviews Rackstraw Downes, Painting is a Metaphor for Hyperallergic
Rackstraw Downes is interviewed for Art21
And you can check out his newest show at Betty Cuningham Gallery
Rackstraw Downes, “Sand Hills with Cell Tower, Presidio, TX, P.M.”(2010). Oil on canvas, 20 5/8 x 35 7/8 inches. (All Images Courtesy of the Artist. © Rackstraw Downes, Courtesy Betty Cuningham Gallery, New York)