View Full Version : Chatter A new camera that allows you to focus after the photo is taken

Bobb Fwed
12-15-2011, 11:07 PM
Here is a new camera (not available until "Early 2012") that allows you to take a photo, then once it is on your computer, define the focal plane. This removes all possibilities for out of focus photos, and removes the mechanisms and the complex software that run the autofocus on modern cameras. Of course it adds a massive amount of software to captures rays of light, rather than pixels. The first versions of this technology developed at Stanford University required a roomful of cameras attached to a supercomputer. Now it is available in this rather small form factor.


An interesting thing is that they label the resolution of the camera in Megarays (11 for this first Lytro), and don't mention what pixel resolution your photos will be (my guess would be much, much lower than 11 Megapixels)..

12-15-2011, 11:38 PM
I imagine this will require a new definition of resolution. Maybe pixels per focal plane?

12-16-2011, 01:14 AM
I'm guessing that these things take a rapid sweep of the entire focal range of the lens, effectively taking a picture at every step the lens can occupy, and capturing all that data in one "shot". Then, chosing the focal point is as simple as selecting the frame that contains that particular focal point.

*IF* all this is true, then 11 "Mega Rays" should translate to 11 Megapixels in the output resolution, but 11 MP * the number of focal frame steps, per image, so if there are say - 100 focal frame steps - then you'd have 11MP x 100 for a filesize... not tiny!

Am I on the right track here, or are they doing something much more magical than I am giving them credit for... :-)


Bobb Fwed
12-16-2011, 01:58 AM
I think its much more complicated, seeing as it required a supercomputer at one point. And it doesn't cycle through focal planes, one of their "features" is instant photo taking, not waiting for focus or any other mechanism, it just samples the sensor, and done.

12-16-2011, 02:44 AM
From the lytro website they state:

Capturing the Light Field
Recording light fields requires an innovative, entirely new kind of sensor called a light field sensor. The light field sensor captures the color, intensity and vector direction of the rays of light. This directional information is completely lost with traditional camera sensors, which simply add up all the light rays and record them as a single amount of light.

That makes things much clearer!

12-16-2011, 02:51 AM
But wait! There's more ..... here (http://www.lytro.com/renng-thesis.pdf). A 203 page dissertation.