As usual, the best light came in the morning and the afternoon. This "best light rule" is a cliché, but alas, mostly true. Mike took pix of oaks in the meadows in the AM and a postcard view of Cathedral Rocks in the PM.
During the day he dayhiked along the Merced River in the vicinity of Happy Isles, seeing some nice backlit leaves.
Photos: Oak, Autumn—Yosemite, 2009; Cathedral Rocks—Yosemite, 2009; Backlit Leaves—Yosemite, 2009