W. Grant Dade
EF2
I am not sure what type of birds are making those rings. It looks as though they are taking off from the north side of Lake Tyler.They were taken with the f4-5.6. I hadn't heard of the f3.5, maybe it wasn't out yet when I was looking to buy.
Noticed you live in Tyler. Check out this link, my first post. One of these rings I'm talking about was very near Tyler. Do you have a guess as to what kind of birds are causing this? One member said it was probably Egrets, roost in huge colonies. Should have been able to see some flying over right after daylight.
Josh
Edit: Oops almost forgot, here's the link to the thread.
http://www.stormtrack.org/forum/showthread.php?t=21395&highlight=expanding+rings
Where did you take those lightning photos. I love the high base. We don't get too many high based storms around here.