After shooting a dozen rolls of bird images with my new EOS 3, I am fairly frustrated of not mastering the ability to judge exposure compensation needs. Based on Art Morris's book, I've only used evaluative metering thus far and not spot. When the sky is overcast, all of my bird images are dark and underexposed. With any sun at all, the whites are blown out. Obviously, I better start applying +/- exposure comp and I incorrectly assumed evaluative would do a fair job. Is the obvious answer to spot meter birds more often or compensate every single shot?