Here are some facts you should know about PDAF in 3rd Gen NEX.

Started Oct 20, 2012 | Discussions thread
privater
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Re: Here are some facts you should know about PDAF in 3rd Gen NEX.
In reply to viking79, Oct 20, 2012

viking79 wrote:

BRUCEK56 wrote:

Hi,

Excellent write up!

Can you explain what the reason would be NOT to have phase detection AF on apertures greater than 6.3?

I thought phase  detection was added to aid in AF accuracy which I would think is even more important in apertures greater than 6.3 because of the shallower depth of field.

It is clear at this point it is added as a marketing feature and not an actual useful feature.  None of the hybrid focus sensors (Canon, Nikon, or Sony) at this point actually do what they are supposed to.

My guess is the system isn't accurate enough to work at larger apertures.  There is much more depth of field at f/7.1 so it doesn't have to do much, and even if it messes up you probably wouldn't be able to tell.

From a practical standpoint, the reason to use PDAF is for focusing on moving subjects (requires large aperture to get high shutter speeds) or in video to prevent focus hunting.  They effectively killed the two main reasons to use PDAF.

Eric

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Sorry for the misinformation, I've update the video on the later post, PDAF it's works on fast aperture, but not work on f6.3 and slow.

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