A word of caution, birds can look odd when faded, worn, or molting! They often look pale-headed, and washed out (bleached) overall, especially the upperside. This makes juvenile Broad-winged Hawks appear more Gray Hawk-like on the face, Red-tails more difficult to assess to race, ageing eagles more difficult, and the list goes on…. Here is an example of a bird Steve Mlodinow shared with me several weeks ago from Colorado. Note how a normally dark bird (particularly the head) such as this juvenile from last year can appear very pale in spring/summer.
I don't want to get too detailed here, just like to keep it easy to digest. And of course, if anyone has questions about a hawk they photographed that looks odd, feel free to contact me and I'll see if I can decipher it.
Update: Here is a bird Cathy Sheeter sent me today. A Red-tailed Hawk from Colorado molting into its first adult plumage, note how pale the head is from fading! Also, check out Cathy's award-winning art @cathysheeter.com