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Old 01-25-2011, 01:25 AM
ravncat ravncat is online now
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Join Date: Aug 2010
Location: Japan
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Quote:
Originally Posted by kencaleno View Post
... Autofocus is only useful for fast sports and wildlife-manual for all else-It's faster and more accurate....
Strictly speaking, I wouldn't say this without some calibration. My d200 is better with AF than MF - and this has to do with the tolerances. LuLa has a good article about this at the moment. It`s a matter of factory construction tolerances, and the optical path from the lens to the mirror through the pentaprism or mirror box and on to the ground glass may have a different length than through lens to sensor, which may also be different from the optical path through the secondary mirror to the phase detectors...

The result meaning - that it`s possible for the image on sensor to not be in correct focus when it is on the focusing screen, or the AF sensors to that effect. So MF may not always be more accurate. It also may change slightly depending on which lens is used. Wide Angles tend to be worse off than Telephotos. (also gotta watch out for those pesky lenses that have a slight focus shift upon stopping down)

Oh how I wish the major manufacturers produced more focusing screen options - optimized for sharpness and DoF over Brightness...
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Last edited by ravncat; 01-25-2011 at 01:27 AM.
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