From what I read, another good field mark for both male and females is in the outer tail feathers the orange edges extend to the base of the feather by the rump (on Baltimore the edge is black at the base of feather near the rump).  In the photos on the internet I looked at, whenever there is a good view of the tail (from above) this seems to be very consistent.  I wonder how close you have to be to see this field mark.

Jeff Shenot
Croom MD