[Universal Creations]

I hope they get around to making a 100-400 zoom some day. There's surely a market... I attended an airplane spotting event today and the crowd was bristling with these (Canon made, of course, in either version). My 70-200 was a definite non sequitur in that setting...

There is one already. It's called the Sigma 100-400. Okay, it's not a Tamron, but it weighs only 1160 grams and is as sharp as the Canon 100-400. The best part: it costs less than half the Canon