Canon EOS 7D -> AF-Probleme! (1)
oh oh ... was Rob Galbraith zum Servo-AF schreibt, gefällt mir aber gar nicht!
http://www.robgalbraith.com/bins/multi_page.asp?cid=7-10042-10239
auf der Seite ganz unten (Zitat)
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Continuous focus using Spot AF, centre AF point, AI Servo and the EF 200mm f/2L IS, tracking a soccer player for a few minutes in fading light, the results showed promise but were ultimately inconclusive: through about 200 frames, the camera was able to hang onto focus properly for portions of several sequences, better than we've ever seen from the 50D, as well as deal with the AF point moving off the subject briefly. But it would also lose focus for several frames for no apparent reason, even when the AF point was right on the mark and the subject was moving at an easy pace. We'll need to give the camera more of a workout than this, however, to see if it will be suitable for peak action sports in particular.
Continuous focus using Zone AF, nine points in the centre, AI Servo and the EF 800mm f/5.6L IS, tracking distant seagulls in semi-overcast light, the results were pretty good. The camera-to-subject distance wasn't changing too rapidly, but the position of the bird within the AF point group was changing constantly, and the camera handled this just fine.
Continuous focus using Zone AF, nine points in the centre, AI Servo and the EF 200mm f/2L IS, tracking a running dog in fading light, the results were terrible. Over about 80 frames the camera got almost nothing usably in focus. If this result is representative of Zone AF, then Zone AF will be the way wrong choice for fast-moving subjects. We had better luck tracking the dog with Spot AF.
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