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回復 29# 的帖子
http://www.robgalbraith.com/bins/multi_page.asp?cid=7-8740-9068
可以參考這個聯結,主要是對焦系統的問題
以下節錄至上面的網頁
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Q. What are the camera\'s autofocus problems?
It has four, all of which are related to the camera\'s autofocus performance:
Under certain conditions, the EOS-1D Mark III has difficulty acquiring focus initially. In a multi-frame burst, the camera will sometimes shoot three to five frames before a moving subject comes into focus, and occasionally a moving subject will not actually snap into focus before the burst is completed.
Under certain conditions, the camera is unable to properly track a moving subject. We\'ve shot numerous sequences of 20+ frames where no more than five or six frames are in focus, even when the AF point has been on the subject throughout.
Focus can shift slightly but constantly at times when the subject isn\'t moving. Under certain conditions, the subject may not actually come into focus through a sequence of frames, even though the point of focus can be seen to be shifting throughout the sequence. This is true whether the camera is set to AI Servo and focus is active throughout the sequence, or when it\'s set to One Shot and focus is activated between each frame.
When tracking a subject that\'s moving somewhat erratically, the camera is far too quick to shift focus elsewhere - to the background or, with a field sport like soccer, to a player passing through in the foreground. With the first three problems, autofocus settings changes don\'t make things better or worse. With this problem, Custom Function III-2, AI Servo Tracking Sensitivity, does have an impact. But regardless of how this Custom Function is set, it\'s not possible to make the camera\'s tracking sensitivity be right. There\'s more on this ahead in the article. |
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樓主: Faust
發表於 2007-10-31 21:51
