I have a friend who has one. I've played with it. As I said when it
first came out "there's no magic, it has to sacrifice resolution to
get variable focus."
The 2005 paper[0] mentions this issue; their bet is that VLSI
progress should eventually yield far more resolution than anyone
knows what to do with, so (just like software people continually
attempt to make computers slower even faster than the hardware people
make them faster) in principle they're hoping to soak up that excess...
And a majority of journalism photos are shot at f/8 or f/11 - the
goal being showing what the scene looked like than to make the
scene artsy or nice looking. I don't know if the Lytro shoots at f/
8 (or even allows setting the aperture).
IMO, the long term future of journalism photos lies in mobile
phones. As demonstrated during the Arab Spring and as currently
being demonstrated in Syria.
My impression is that mobile phones are essentially set up under the
philosophy of "f/8 and be there"; the CCD helps with DOF and the
modal use case being "here are my smiling friends in front of X"
practically demands that focus be wide.
Apart from the focus-pull gimmick, I'm drawing a blank on consumer
uses for light field cameras. It could be very useful in microscopy
(in mineralogy and petrology it would already be interesting to
recover 3D-structure by sweeping a narrow synthetic focus plane, even
more so when the synthesized plane can be tilted; I have to imagine
that for biologists, whose subjets move, this might be even more
interesting), but in most consumer photography, the objects are
opaque at the wavelengths of interest. Surveillance is another
obvious use[1]; synthetic aperture techniques were developed because
when the subjects are not particularly keen on being observed they
have a great relative motion to the camera, and often a separation
well outside of spitting distance, but consumer photography normally
has willing (if not posed), close, relatively stationary[2] subjects.
OK, not completely a blank: possibly useful for small children and
animals[3].
-Dave
[0] http://graphics.stanford.edu/papers/lfcamera/
[1] would synthetic focus be useful for isolating faces in crowd
cameras? for range estimation?
[2] hmm... sports? are there any sporting events which are not
already well illuminated enough for a fast telephoto?
[3] OTOH, I'm fairly happy with a steinbock we got using binoculars
in front of a mobile phone; didn't even have to 'shop in the lens flare
cf http://bit-player.org/2012/light-field-photography