Thanks to Dennis for starting this thread.? My primary interest in "birding" is photography.??? I'll start by telling what I use and why.

Camera = Canon 7D.? MSRP = $1,700
Lens =???? Canon's? EF 100-400 zoom (f/4.5-5.6L) with? IS and USM.? MSRP = $1800.

I have found this combination to be a very "economical" (cough, cough) package in the sense that Canon's high quality straight telephoto lenses start at $1,400 for a 300mm and rise sharply ($5,000 on up) if you want to get a very high ( or is it low?) f stop of? 2.8 or less.

Why?do?I use the lens?I do??? Costs (discussed above) and versatility.? The zoom lets me back off? if I want to take?shots of the scenery??or when I am trying to locate a hard to find bird that is close to me.?? I have also blown some shots of the Edmonds eagles when I forgot to back?off to 100mm from 400mm as the?eagles passed?very close?over head.??

Depth of field (DOF) is a problem for me, especially when shooting large raptors like the Edmonds eagles,?so I try not to shoot with an f stop?less (greater?) than 7.1.?? Therefore,?I don't need an f stop of 2.8 offered by the more expen$ive?straight?telephoto lenses in the 300-600mm?range.????

John mentioned the image stabilization (IS) problem when shooting flying birds.?? My Canon?100-400 zoom has two IS settings.? Setting #2 is?specifcally for photographing objects moving across the field of view and is what I use when shooting hand held. ??

I have a good tripod, but?I use it less and less.?? My prefered method of photography is "walk and stalk."???My camera/lens setup isprobably about the heaviest I care to?carry and still?take hand held?photos which are not blurry.

I am still trying to overcome the problem of maintaining focus on?flying birds.?? I use the A1?selection in autofocus (AF) mode, which is supposed to lock on to a stationary target ?and stay focused on that target once it starts moving.?? Unfortunately, many of my shots are blurred when the AF locks on to something behind?a flying bird, such as a cloud, ferry dock, Puget Sound, etc.?

As I stated in an earlier post, I?like the 7D because of its Q screen feature, which?makes it easy to switch ISO/shutter speed/aperature? setings,? I am constantly adjusting these settings dependent on the light and the bird.
Bill Anderson; Edmonds, WA.