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Old Dec 7, 2010, 2:16 AM   #1
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Default Pentax K-X Focus options

Hi All,

Can you tell me the different between A.F.A and A.F.C. on the pentax k-x? For whatever reason, once in a while I will have a few pictures that is out of focus. Maybe I am moving around too much, hand shake too much. But which one should I be using.

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Old Dec 7, 2010, 2:17 AM   #2
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Maybe I post this message under the wrong topic, but I don't know how to move it.
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Old Dec 7, 2010, 3:41 AM   #3
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There are three focus modes:
  • AF.S (Single mode) - When you press the shutter button halfway down, the camera focuses on the subject and locks focus. You can't take a photo unless the focus is locked.
  • AF.C (Continuous mode) - When you press the shutter button halfway down, the camera focuses on the subject, but unlike AF.S, if the subject moves, the camera will continue to focus on it. You can take a photo even if the subject is not in focus. AF.C is not available in 'Live View'.
  • AF.A (Auto) - This mode switches between AF.S and AF.C, depending on the subject.
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Old Dec 7, 2010, 9:20 PM   #4
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So, with AF.C, if the subject move, will the focus automatically follow the subject or not?
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Old Dec 7, 2010, 9:36 PM   #5
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Yes, AF-C will track and try to predict where the subject will be when the picture is taken, and should get it right if the movement is predictable. Doesn't always work.
If you can post a photo showing the problem, it would help, as motion blur from camera shake, or subject movement, if shutter speed is not high enough may also be part of the problem.

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Old Dec 8, 2010, 3:55 AM   #6
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basically if your shooting something like a landscape or a posed portrait then AF-S is what you should be using - if you at a rally or something and tracking cars coming towards you or someone running past you etc then AF-C is what you should be using

neither is better than the other they just are used for different things
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Old Dec 8, 2010, 6:28 AM   #7
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Remember that, in 'Live View', AF-C doesn't work. So if you're using 'Live View', and your subject moves, it may be out of focus.
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Old Dec 8, 2010, 9:46 PM   #8
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Thanks for the help. I don't really use the Live View anyway. I only use it to view pictures. I find that it take a LOT longer to focus when using Live View. So, I just been using the view finder.
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