Originally Posted by Joseph Clark
So, Dave, are you saying that an HDMI device like the PS3 would likely introduce some flicker into the display, because it would send only a 120hz signal (60hz to each eye)? And I'm not sure what you mean by flicker in this context. Are you talking about 3:2 judder? Or are you saying a 48hz signal to each eye would create a flicker? Any links where I can read the details?
the "flicker" issue has to do with the LCD shutter glasses and how many times a second they need to "black out" the image feed to each eye. Most people can detect the flicker produced by an on/off image alternating at 60 times a second... basically what you have when you think of a "stereo" image running at 120 Hz since that's 60 Hz per eye... meaning 60 times a second each eye is turned off while the other eye is turned on. That's good but not great.
Think about this: can you see flicker in a movie-theater? that's a good example of 48 Hz flicker as the film shutter shows each image twice but has to close in between to advance the film frame.
PAL TV viewers typically see flicker with the 50Hz cycle of their PAL sets as well. 60Hz is good but not great either... which is why computer monitors typically start at 72 Hz. None of this is unique to 3D issues... just google about flicker and frames per second.
Back to 3D... so assuming that some folks will see flicker with only 60 Hz per eye...
By upping to 240 Hz total, you could give each eye 120 Hz.
By upping to 480 Hz total, you could give each eye 240 Hz.
At that level there should be no perceived flicker of any kind by any viewer.
Now... the way this is affected by HDMI 1.3 versus HDMI 1.4 all depends on the TV set... you see, using HDMI 1.4 the 3D signal is sent at the lowest bandwidth needed to send the original 1080p24 image pair... which means 1080p48 since 48 is 2 x 24 (left and right 24 = 48 total). Then the TV does with that whatever it wants to give you the best image, since HDMI 1.4 3D TVs will be sure to "know" the left and right video stream contained in that 1080p48 HDMI 1.4 signal.
What is not sure is how older "3D ready" sets will work with a signal over HDMI 1.3. Some of these sets are "dumb" and will basically just show you what you give them... so one way to make some of them work is to feed them a left/right/left/right image at 120 Hz and they'll just blindly sync to it. That only gives you 60 Hz per eye.
However, if the "3D ready" set is "smart" and can actively identify the left/right stream and then apply its own internal up-sampling, you could end up with the same high qualtiy result as with an HDMI 1.4 TV.
The other issue is resolution: some "3D ready" sets aren't really able to provide full 1920 x 1080 resolution per eye when in 3D mode... others will.