The goal of autofocus is to make something in the picture come out sharp. But if you're taking a photo of people, it's not their hands you want in focus. Recently, camera makers have been adding the ability to detect faces in a scene, track them if they move, and optimize both focus and exposure to make everyone look their best. But not all face-detection systems are equal, as I discovered after testing several compact cameras
on patient friends who posed by indoor light, as well as on passersby rushing through Times Square.
How it Works
All face-detecting cameras compare the scene before them to a built-in library of features derived from images of real people, such as the distances between eyes, patterns of light and shadow, and skin colors. So far, no models can identify a face in profile, and they don't function well in low light, such as in bars or candlelit rooms. But they're not easily fooled: In our tests, none were thrown off by variations in skin tone or by accessories like eyeglasses.
Face-Tracking Face-Off
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Fujifilm Finepix F40fd |
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Sony Cyber-shot DSC-W80 |
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Nikon Coolpix S200 |
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