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Old Jan 13, 2008, 9:53 AM   #5
JohnG
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Join Date: Aug 2004
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Mike,

Just to add to Jim's excellent response:

One aspect that is critical to sports shooting that NHL's charts don't point out is how well a focus system TRACKS. Initial focus lock is extremely important but it's the system's ability to TRACK that is important. And I say system because the body must predict the path of the subject and either the body or lens must focus. So it's both the body and the lens.

I've seen some very positive comments about the A700 and some positive comments about the Oly E3 but in both cases I haven't seen any type of volume of sports shots. It's difficult to draw conclusions based upon just one or two person's experience. Sony has the benefit of the Minolta background which has always had good focus systems. Canon & Nikon have the benefit of most of the worlds sports shooters to test their systems. For others it's a little more challenging to develop pro grade action focus systems because they don't have the army of testers, QAers and such. If I was going to trust in any system but Canon or Nikon it would probably be Sony because of the Minolta background. The only problem I have with them is the prices on their pro grade lenses. It could be argued my canon lenses are overpriced but Sony makes them look cheap. While they are arguably outstanding lenses it seems that if most of the world's pro sports shooters can get by with less expensive Canon gear (followed by Nikon) - the question becomes - is Sony offering a better overall solution for the higher price?

Having said ALL of that - sports shooting takes practice and technique. Especially in low light. I've never shot Sony / KM DSLRs but after having a Canon 300d, 20d and now 1d I can absolutely say each model was a huge improvement over the lesser model in terms of focus speed/accuracy. I would expect the same will be true of Sony.

But don't discount the lens in the equation. Just because a lens has a wide aperture doesn't mean it focuses fast. Typically a lens with it's own focus motor will focus faster - and even then, not all lenses are created equal. The perfect example from canon is the 85mm 1.8 vs 85mm 1.2L. The 1.2 is an 'L' lens while the 1.8 is not. It has a wider aperture, yet it focuses slower than the 1.8. So it's a less effective sports lens when focus speed counts (note some sports focus speed is more critical than others). In short, there are a LOT of variables that are in play. That's why using a chart like NHL posted is dangerous
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