Vesper Sparrow, you can see a hint of the rufous shoulder patch, not often visible.
A beautiful bird we saw at while birding at Kennebunk Plains Wildlife Management Area was the Vesper Sparrow. Vespers were common here, because they nest in grassland habitat. I was able to get some nice photographs of them from many angles. One of the key clues to their identification is the white outer tail feathers and white eye-ring (less obvious on these worn birds) on this largish sparrow with streaked breast and back. Vespers are named for their twilight singing (although they're not the only bird that does this.)
Sparrows are beautiful and challenging to identify. You need to get into subtlety, since most sparrows are shades of brown, and appreciate how wonderful they blend with their environments. We enjoy that.
I took the photos with my Canon 1D Mark IV camera, my 500 mm lens and a 2x teleconverter, thus I had the equivalent of a 1000 mm lens, which helps to get closer shots of these birds.