Using distance info gleaned from the phone's dual cameras, and a bit of computational wizardry, the phone would blur the background of a portrait subject.
depth of field or "DoF" in photography jargon) of a picture are determined.
Basically, the smaller the sensor and the smaller the aperture relative to it, the less background blur (or bokeh) you're going to get at normal portrait distances. And cell phone cameras and point&shoots have tiny sensors and relatively small apertures. Generally, the only way you'd see significant background blur in a head-and-shoulders portrait would be with a DSLR-sized sensor, so those sorts of photos got subliminally tagged as "taken with an expensive-ish camera by someone who at least considers photography a bit of a hobby."
Huck shot with a Fujifilm X-E1, which has an APS-C sized sensor, like you'd find in a DSLR, using a Zeiss Touit 32mm f/1.8 lens shot wide open. |
If you've seen older manual focus camera lenses, that is, by the way, what that hockey rink's worth of painted lines are for. On some lenses, Nikon even color-coded them to make reading them easier. If you look at the zoom lens below, you'll notice the aperture numbers are color-coded. If you set the aperture and then focus the lens on an object, the two colored lines will point to the nearest and farthest in-focus distances on the lens's distance scale.