Had I hit that lottery, I could have bought both of us HUGE lenses, but for now, my luck will have to do...Hey, but seriously, I certainly know where you are coming from. And bird photography, to me has got to be one of the most challenging things to shoot. I admire anyone that goes out in the fields and waits the whole day for that one great shot. I know how hard it was for me to just set up my little tent in the back yard last winter just waiting on the local birds, I nearly froze because I was so stubborn and didn't know when to come indoors. I don't know if I could trust myself to go out looking for the birds of prey that are so beautifully caught in national geo. They would be prying me out of the tent. My hats off to you my friend, and tell your students for me, they have one FINE teacher.