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Why 3D Doesn't Work and Never Will (2011)

rogerebert.com

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Re: Why 3D Doesn't Work and Never Will (2011)

#71

Post by dTal »

TheZenPsycho wrote: post #17

Actually, the convergence problem is theoretically solvable with a light-field projection system. That is, instead of having 2 images that are simply "fed" into each eye but projected onto a flat screen that is not converged with the 3d disparity "information" contained in the images, you have a system where the screen emits a light field that your eyes can focus on at any depth. We already have consumer level light…

If the screen were retroreflective, wouldn't all projected light end up back in the projector by definition?

Re: Why 3D Doesn't Work and Never Will (2011)

#72

Post by erichocean »

blueskin_ wrote: post #62
joshvm wrote: post #61

3D is fine, it just needs a few things: 1) High frame rate - really, enough of this "24fps looks better" nonsense. We can make adaptive frame rates if need be. This kills the nasty tearing you get when cameras pan, particularly noticeable over fancy landscape scenes. 2) Brighter projectors - don't know why this isn't the case already. 3) Actually shot in stereo. There's a very good chance that the last 3D movie you s…

>enough of this "24fps looks better" nonsense. We can make adaptive frame rates if need be. I don't even understand the 24fps logic, as all it causes is tearing and motion blur. We need better framerates, but across the board, not just in action spots, as 48/60 give smoother motion overall. The Hobbit was 48fps; I bet most people either didn't notice, or thought it looked better. Certainly, there was no appreciable m…

The Hobbit was 48fps; I bet most people either didn't notice, or thought it looked better.

I, and everyone in my family, thought it looked terrible at 48fps and in 3D—like a mid-80s BBC soap opera. I didn't see the 2D version, so maybe the film itself just sucked even in 2D.

There's a very good chance that the last 3D movie you saw was depth-ified in post process. Shooting in 3D is expensive and requires more editing, calibration etc, so people don't like doing it.

This is just flat out wrong. "Depthifying" things in post produces better 3D, full stop, because a single 3D depth works poorly across the entire image.

Every. Single. Animated. Film. uses multiple 3D depths in the same shot, which is what "depthifying" allows you to do, and that's a huge reason why animated films have the best 3D currently. If you just shoot 3D in-camera, you're forced to choose a particular 3D depth and the results, in most shots, are sub-par.

BTW, my information comes from talking with actual 3D supervisors in Hollywood (where I lived) and the cml-3d list, which is where the people who actually do this shit for a living hang out and talk about the 3D releases as they come out, the techniques they used, and why. If you're curious about the craft, you could do worse than signing up for the mailing list and listening in on the conversations happening there.

Re: Why 3D Doesn't Work and Never Will (2011)

#73

Post by blueskin_ »

erichocean wrote: post #72
blueskin_ wrote: post #62

Earlier quoted context omitted.

>enough of this "24fps looks better" nonsense. We can make adaptive frame rates if need be. I don't even understand the 24fps logic, as all it causes is tearing and motion blur. We need better framerates, but across the board, not just in action spots, as 48/60 give smoother motion overall. The Hobbit was 48fps; I bet most people either didn't notice, or thought it looked better. Certainly, there was no appreciable m…

The Hobbit was 48fps; I bet most people either didn't notice, or thought it looked better. I, and everyone in my family, thought it looked terrible at 48fps and in 3D—like a mid-80s BBC soap opera. I didn't see the 2D version, so maybe the film itself just sucked even in 2D. There's a very good chance that the last 3D movie you saw was depth-ified in post process. Shooting in 3D is expensive and requires more editing…

>This is just flat out wrong. "Depthifying" things in post produces better 3D, full stop, because a single 3D depth works poorly across the entire image.

No, you're flat out wrong. Again, would you colour in a black and white film in postproduction and expect an accurate result?

As movies normally create depth by blurring objects at different distances to mimic the human eye, this interferes with actual focusable depth if it is postprocessed into 3D. It is possisble to do it right, but it takes the best part of a year (see: the 3D-ifying of Titanic), not two weeks like Disney moview or Clash Of The Titans took.

Point taken about animated films usually having better 3D, but that is exactly because it's easier and cheaper to produce natively.

Re: Why 3D Doesn't Work and Never Will (2011)

#74

Post by TheZenPsycho »

dTal wrote: post #70
TheZenPsycho wrote: post #26

Earlier quoted context omitted.

I want to be clear that not any of this is easy . I think as soon as you try it, your first attempts are going to be very blurry, squint inducing, and especially very dark. A lightfield display, in order to achieve the same level of perceived brightness as a traditional 2D display, needs to generate 2-10 times (perhaps much more) more actual light, with all the requisite power requirements that entails, since the lig…

Why would it need to generate more light? Suppose you told your lightfield display to simply display all white - wouldn't its light distribution be the same as a white LCD, hence taking the same amount of power?

In a projector system you generate light, and then you block it using either photographic film or LCD to produce the image. A lightfield display can be thought of as a 2D, higher resolution generalisation of a lenticular ("no glasses") display, or for example, the display of the 3DS.

In these kinds of displays, you have a light generator (LED or flouro or reflection) with the same surface area as a normal print or display. But to produce the directional light, for say the left eye, you must block the portions of the image that relate to the right eye from the light travelling to the left eye. And vice versa. This halves the amount of light for 2 directional images. thirds it if you want 3. So you end up with an image that is much darker then normal. you must compensate by generating 2 or 3 times the amount of light. This problem gets worse the more "views" you add on. So if you want 10 omni directional views you have to generate enough light for all of them, since, even if you set everything to "white", as you suggest, most of that white is getting blocked from your view.

Or to put another way, you get allocated a smaller source 2d image plane surface area to generate your viewpoint.

Re: Why 3D Doesn't Work and Never Will (2011)

#75

Post by dTal »

TheZenPsycho wrote: post #74
dTal wrote: post #70

Earlier quoted context omitted.

Why would it need to generate more light? Suppose you told your lightfield display to simply display all white - wouldn't its light distribution be the same as a white LCD, hence taking the same amount of power?

In a projector system you generate light, and then you block it using either photographic film or LCD to produce the image. A lightfield display can be thought of as a 2D, higher resolution generalisation of a lenticular ("no glasses") display, or for example, the display of the 3DS. In these kinds of displays, you have a light generator (LED or flouro or reflection) with the same surface area as a normal print or di…

Why do you have to block the light? Sure, primitive stereo parallax barriers like the Nintendo DS has do, but nobody uses parallax barrier tech for any proper lightfield application. The system you mentioned, a lens array over a high-PPI screen, blocks nothing; light is only refracted. Ergo, the energy required to run the screen is the same as without the lens array, e.g. a normal screen.
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