You could be forgiven for thinking I had mistyped the title of this blog post. Many people would know that cameras rely upon the user focusing upon a subject or a particular field in a shot prior to capturing a picture (most notably with SLR cameras). Otherwise, you end up with a blurred photo with little you can do after the fact. Putting aside the use of Adobe Photoshop and other tools you really need to get the best possible shot at the time of capture.
So how do current digital cameras work?
At a simplistic level, digital cameras simply capture the pixels comprising an image that hits the sensor inside the camera. Colours, lines and curves are captured “as is” as well as the current state of focus across all of those pixels. As obvious as it sounds, a photo taken with current digital cameras is a static snapshot that, in its original form, cannot be refocused after the fact (requiring a brand new photo to capture the change of focus). The photo is treated as a single beam of light.
Sure, you can tweak the colours and contrast but things such as depth of field are a completely different matter.
So what makes a Lytro camera any different?
The Lytro camera incorporates a new type of sensor called a “light field” sensor. To try and put it simply, a light field represents how a particular point of view appears through the amount, colour and direction of light traveling through it. So rather than just capturing a copy of the image that hits the sensor a light field camera captures all of this extra information instead. This allows a scene to be visually recreated as it existed at the point of capture based upon all of these individual paths of light instead of a two dimensional grid of pixels.
I guess you might be wondering what the benefit of using “light field” sensors over a standard sensor might be?
Well, coming back to the title of this blog post, this technology allows a photo to be refocused after it was shot through the use of software processing. If you wanted to change the focal point from something in the foreground to something in the background you can do it quite easily. With the demo below, you can click on any part of it to refocus the picture at that point. Try clicking on the foreground flowers on the left, then the ones on the right and finally the hills in the background.
Another (arguable) benefit of plenoptic photography is that a scene can be captured in 3D. I’m still figuring out how this works and whether or not this requires two lenses to work or the combination of images from different vantage points but it does seem to be possible.
Anyway, images captured with a Lytro camera become “memory points” instead of just a static snapshot. I’m not a hardcore photographer by any means but I think this sort of technology really does have the potential to bring professional grade photography to regular people. That said, cameras such as the Lytro camera probably won’t come cheap initially much like the original digital cameras were when they first came out but it will signal the beginning of what I reckon will be a new and exciting chapter in digital imagery.