Today’s light field processing algorithms have mostly been tailored for relatively low image resolutions in the range of a few megapixels. That means, even with increasing sensor resolutions, light field technology will still be effectively limited by resolution. The analysis of light fields at high spatio-angular resolution, so-called “gigaray light fields“, remains a technological challenge due to the sheer computing power it requires.
Researchers at Disney Research in Zürich, Switzerland, have come up with a new, faster way of processing such light fields. Their secret: ignore some of today’s established practices in image-based reconstruction, and try something different.
Light field photography is very exciting, but so far, the options for consumers are very limited. You can either get an affordable dedicated light field camera (coming with its own set of drawbacks), or go for a custom DSLR modification that is pointed at the professional and industrial market and basically out of reach for typical enthusiasts.
Recent news of a new Olympus patent for a Micro Four-Thirds plenoptic adapter have already shown that it might not be so long until we can upgrade interchangeable-lens cameras on a flexible basis. At this year’s SIGGRAPH conference, set to take place next week in Anaheim, California, Researchers Alkhazur Manakov and colleagues from Saarland University (Germany) will be presenting a new, addon for ordinary DSLR cameras, that will achieve even more than “just” light field capabilities.
At its current development stage, light field photography (based on microlens arrays) poses a compromise between spatial information and resolution: The more refocus or prespective a camera is required to provide, for example, the more of its sensor resolution is sacrificed. In the Lytro Light Field Camera, an 11 Megapixel sensor takes pictures that result in pictures of 1.1 Megapixels, so only about 10 % of the sensor resolution make it into the final image.
As reported previously, the MIT‘s Camera Culture group has come up with a new method to capture light fields, which is both cheaper and more effective. In a new article published by MIT News, the researchers explain what their system, named “Focii”, is capable of:
At this summer’s Siggraph — the major computer graphics conference — they’ll present a paper demonstrating that Focii can produce a full, 20-megapixel multiperspective 3-D image from a single exposure of a 20-megapixel sensor.
So you like the interactive Refocus feature of Lytro’s LightField Camera, but not its 400+ $ pricetag?
There’s a way to achieve the same effect using an ordinary DSLR or Compact System Camera (interchangeable lens camera), and in this post, we’ll tell you how to do it!
Making your own DIY LightField Camera is not very hard, provided that you have a DSLR camera with detachable CCD back.
One of the things that may be hard to get is an array of microlenses – e.g. the cosine film mask we mentioned in our earlier Do it Yourself post is virtually impossible to come by these days.
Microlense sheets are available at reasonable prices from a few sources, but their specifications may not be ideal for your camera or image sensor (e.g. size, focal length, …).
That doesn’t put off real LightField fans, though: Mats Wernersson shows you how to create a microlense array yourself.