6.34.2 Smile Shutter

Here’s another variation on the same theme. If you can detect that a face is in the picture, you can also look a little closer and tell if that face is smiling. And you can tell the camera “Yo! Don’t wait for me to push the button. Take the picture as soon as you detect someone is smiling!”. And so, with autofocusing enabled, if you invoke Menu --> 6 --> Smile / Face Detection --> Smile Shutter ON, the camera will constantly analyze the scene and it will not rest until it finds a smiling face and takes the picture. You can even adjust its sensitivity by using the Left and Right arrows to choose between Big, Normal, or Slight Smile. This feature can really come in handy when you’re taking self-portraits.

When you enable Smile Shutter, you see a vertical scale on the left, indicating the strength of the smiles it detects. And you don’t have to press the shutter release button halfway. Just point the camera in a general direction of a face. When the camera sees a face, the vertical scale on the left springs to life, and the camera starts to focus on any faces it finds. When the “smile strength” is higher than the currently-set threshold, (that white triangle to the right of the vertical scale), the camera takes the picture. It will continue doing so until you disable the feature by turning the camera OFF (when you turn it on again the function defaults to Face Detection ON – Registered Faces). Try enabling this feature and shooting some family photos you have hanging on the wall. It will give you a very good feel for what works and what doesn’t for this feature.

Smile Detection is hard to do algorithmically (although not as hard as recognizing a registered face), and so in order for it to work properly you have to help the camera out a little. The face has to appear rather large in the picture (it won’t work with a face that’s a mile away, for example). The face can’t be obscured – that is, no sunglasses, no hats, or anything else that would give the image recognition algorithm a hard time. And even if the camera detects that there is more than one face in the picture, it doesn’t wait for both faces to smile – only one face will trigger it. (That’s why I said this feature was great for self-portraits but not necessarily for group pictures.)

Figure 6-76: The smile shutter is an interesting feature but is easily fooled. (It triggered all of these pictures!)

Some additional details about this feature you ought to know:

• Smile Shutter is also a real energy hog – the camera is constantly on a high state of alert, analyzing the live view stream and staying on regardless of what you have Power Save set to.
• Invoking Smile shutter automatically activates wide area AF and single-shot.
• It’s not selectable if you’re in Manual Focus mode.

TIP: I haven’t tried this myself, but reader Tim Boyle suggests using Smile Detection at a party – just put your camera on a tripod, set your lens to “Wide”, ensure that the battery is fully charged, and let the camera shoot whatever smiling faces it sees!