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HDR Video a Reality
akaru writes "Using common DSLR cameras, some creative individuals have created an example of true HDR video. Instead of pseudo-HDR, they actually used multiple cameras and a beam splitter to record simultaneous video streams, and composited them together in post. Looks very intriguing."
Can anyone give a brief rundown on what HDR is? I know it stands for "high dynamic range", but as someone who knows nothing about photography, it means nothing to me. What it has to do with overexposure/underexposure (to which the video refers)? Why is it harder to do with video than still images?
You forgot about full lightfield capture. This can be done with a single camera using ultra high resolution and a microlens array (or alternatively, an array of a very large number of tiny cameras). Think single camera, single shot capture of depth (3D) and all focus planes. Then you can reproduce the full 3D and multiple focus depths (as in, the eye would have to focus at different depths) on a flat display with microlens array covering it (again, need ultra-high resolution since focal depths and parallax viewpoints are discretized to the pixel number covered by each micro lens).
"Politicians and diapers must be changed often, and for the same reason."
With frankencamera you could do HDR and a lot more things in an "intelligent" camera with software. In fact the first implementation in a mass consumption device was in the N900, it takes several photos, regulates exposition and other parameters to make that photo in a more parametrizable way that the iphone could do. But not sure if that would be enough for HDR video, if needs that the input, in real time, have different something at hardware level. In that case maybe something like this 3D camera would be needed. And could give some meaning to such devices... not only shooting in 3d, but in HDR video.
It's the other way around.
Even though we call it high dynamic range in videos and photographs, it's actually just compressing all the extra information from multiple exposures into a LOWER dynamic range, so we can manipulate/display it on our 8-bit screens.
Games, however - such as the Source engine after it got the HDR update with Half-Life 2: Lost Coast and Day of Defeat: Source, actually do increase the dynamic range of a scene beyond what your monitor can display. They underexpose and overexpose parts of the scene when transitions between light and dark places occur, just as your eyes would before they adjusted to the new light, or as a video camera would depending on what exposure the videographer chose. This makes it look more realistic - just take a look at a bright outdoor scene in Half-Life 2: Episode Two and check out how shiny objects in the sunlight have blown-out highlights that gleam brilliantly, and then look at the same scene in the original Half-Life 2, where that object would look flatly-lit and fake. The "non-HDR" looks more fake because the dynamic range is compressed so you can see all the detail everywhere, which also gives it that flat "game" look.
Of course, that last part is just my opinion - but I believe that in order to look more realistic, CGI needs to simulate the behavior of traditional cameras with a lower dynamic range (or that of your eyes before they've adjusted properly to bright/dim light). The everything-is-exposed-properly, compressed-dynamic-range look just appears fake to me, even though my eyes could probably perceive that range at the actual scene. I'm not sure why.
WHO NEEDS SHIFT WHEN YOU HAVE CAPSLOCK/ DAMN1