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#1 Jim Nelson

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Posted 02 May 2009 - 11:21 PM

Hi,

What are the problems when you use the auto functions of a camera (auto focus, auto white balance, auto exposure etc)?


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#2 Jim Nelson

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Posted 02 May 2009 - 11:34 PM

And also what is the problem when you use auto focus and the subject moves in the frame? What I mean here is that he always stays in the center of the frame but changes distances from the camera. Will the auto focus always focus on him properly?


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#3 Brian Drysdale

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Posted 03 May 2009 - 03:49 AM

And also what is the problem when you use auto focus and the subject moves in the frame? What I mean here is that he always stays in the center of the frame but changes distances from the camera. Will the auto focus always focus on him properly?


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This isn't the correct sub forum for this question. Students and First Time Filmmakers would be the place, since this question hasn't anything to do with Cinematographers.

Regarding auto, the problem is that everything changes as the camera sees fit, depending on how the content of the frame, colour temperature and lighting levels vary

Given an average subject not doing an actions that may confuse the auto focus, whilst framed in the centre the subject should stay in focus. If they don't stay in the centre, there's a good chance that the wall behind the subject will be in focus.
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#4 Hal Smith

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Posted 03 May 2009 - 12:21 PM

A good example of autofocus screwing up the shot: Shooting a nest full of Red Shouldered Hawk chicks up about 50' up in a tree with an HV-20 with my new Canon tele-adapter on it and the camera in autofocus. All the while not noticing the small branch slightly in front of the nest...that the autofocus was zeroing in on, resulting in a slightly soft shot.

Happened to me yesterday. My lesson? Buy a Marshall HD monitor so I can see what the h*ll is going on shooting with long focal lengths, the built-in monitoring is not up to seeing the limited depth of field available shooting with the telephoto adapter.

PS: The chicks are getting close to first flight age, I got some awesome shots of momma and poppa perched in trees about fifty feet away calling to the chicks to coax them out into the larger world. Avian good parenting in action: First they "Parent to Protect", then they "Parent to Prepare".

PPS: Asking about autofocus and the real world IMHO is more than a Student/Newbie question. The only sub-Forum it might have been better in is General Discussion.
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