Blurryeyed wrote:
Both those images seem to be backlighted which means that you are having to push exposure, if the lighting were more optimal (coming from the front) I am sure that you would be much happier with the quality of the image. If you are really serious about birding and are wanting to see detail in feathers you are probably going to have to invest in a better lens, there are fine offerings from Sigma and Tamron, but for me the Canon 100-400 II is hard to beat.
The lighting is coming from the up and to the right. So in the case of the hawk over the left shoulder. But there is a white fence in the background that acts like a reflector.