I just bought a Canon 70-300 DO IS lens used on Amazon for $580. So far, so good.

What spurred this purchase was the failure last weekend of my previous long zoom (a Sigma 70-300-- conventional motor, rotating front barrel, decent, but not great, IQ) to achieve focus-lock when I was trying to photograph my young cousins getting their high-school diplomas. This always was a lens that had issues focusing quickly and getting focus lock. I found myself forced to use it because the general seating was way in the back of the auditorium. I expect I'll be selling it and a few other pieces of gear I'm not using much in the near future.

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So far, the DO focuses a lot quicker and more surely than the Sigma. (It also doesn't sound like it's grinding coffee.)

I just bought a Canon 70-300 DO IS lens used on Amazon for $580. So far, so good.

What spurred this purchase was the failure last weekend of my previous long zoom (a Sigma 70-300-- conventional motor, rotating front barrel, decent, but not great, IQ) to achieve focus-lock when I was trying to photograph my young cousins getting their high-school diplomas. This always was a lens that had issues focusing quickly and getting focus lock. I found myself forced to use it because the general seating was way in the back of the auditorium. I expect I'll be selling it and a few other pieces of gear I'm not using much in the near future.

So far, the DO focuses a lot quicker and more surely than the Sigma. (It also doesn't sound like it's grinding coffee.)

I just bought a Canon 70-300 DO IS lens used on Amazon for $580. So far, so good.

What spurred this purchase was the failure last weekend of my previous long zoom (a Sigma 70-300-- conventional motor, rotating front barrel, decent, but not great, IQ) to achieve focus-lock when I was trying to photograph my young cousins getting their high-school diplomas. This always was a lens that had issues focusing quickly and getting focus lock. I found myself forced to use it because the general seating was way in the back of the auditorium. I expect I'll be selling it and a few other pieces of gear I'm not using much in the near future.

So far, the DO focuses a lot quicker and more surely than the Sigma. (It also doesn't sound like it's grinding coffee.)