Originally posted by caliscouser Frankly just a better fact detection implementation would be useful for a lot of people right now.
I like face detection on my D800, If I am shooting events or people it is very handy what nice about it is that you no longer have the need to focus and then recompose or have to fiddle with moving the focus points around.
How they have it implemented with the D800 if the face fall within the AF coverage the camera will select that face and highlight the AF point's the face fall under, this way you have real time feedback on what the camera is focusing on. If the camera looses the face lift you finger off of the AF and press it again
For the timed I need eye AF detection 3D tracking is the next best thing when using the 150 2.8, place the eye under the AF point and let the camera track the eye for you and you never have to move the AF points around as you compose the shot or when the subject moves around. And again you have constant feedback in the viewfinder as to what is being focused on and just like with face detection all you need to do is lift your finger off of AF and then relock on the target.
Some may feel that they would never use the feature, the funny thing is 20 years ago I felt the same about AF
If you are under the gun and the feature aids in your every day work why not use it, it also free you up so that you can focus
on other aspects of photography so why not hand off focusing on the face to the camera just as we have handed off AF, metering, and spot metering to the camera.