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Old Dec 13, 2007, 9:49 PM   #24
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JimC wrote:
Quote:
Even if a camera loses focus during tracking, very little movement of the optical groups for focusing may be required for a new lock , since the focus distance hasn't changed much from the last lock (unless it tries to lock on the background instead). lol
I agree - That why I said "In the worst case if the AF has to be re-acquired every frame" and "Granted tracking will require only smaller steps, but if a subject falls out of an AF point entirely..."

-> But remember we're talking about a moving subject which is not staying still for the AF point to work on, beside the contrast also plays a big role beside good lighting like a "sunny" day... (the AF point could land on a blank part of the jersey for example)



Quote:
... very little movement of the optical groups for focusing may be required for a new lock...
Yeah - but doesn't this hold true to every camera in tracking, be it Oly or Canon? :idea:
-> while other camera may have up to 200ms (5fps) to perform this little adjustment in optics, the 1DmrkIII has to do it in 1/2 the time (i.e. 100ms) to keep up its frame rate; However, according to the initial lock result the MrkIII AF algorithm is not any faster, but actually slower (down to EV-4 like on the Sony)!!!
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