I've only got 3 right now too... the Canon 17-40 f/4, Canon 10-22 f/3.5-4.5 and a Sigma 105mm f/2.8 macro (which actually focuses to infinity quite fine too and makes for a sharp portrait lens). I plan on plunking down the big money on a Canon 100-400mm in December. If you'd like to swap or borrow something for a week or a day let me know. I remember a couple of the initial homework assignments involved depth of field study, and the 105 2.8 is excellent for that (since also being a macro lens it stops down to get huge dof as well as being a bright and narrow 2.8 wide open). I'm serious about going on those field trips too... so the weekend after next... and if its cades cove it would have to be on a sunday since the park is closed to motor vehicles on sat morning. I didnt get to do the cades cove trip last time. Keep in touch about that :)
- Steve