Originally Posted by namechamps
For LCD & Plasma are there any 1080P displays that have 24fps and apply 5:5 to generate a 120Hz output?
-No there's not, and its REALLY dissapointing that there's not...
The Pioneer Pro FHD1 will accept and display 24fps input and display it as a multiple of 24 (which is pretty commendable by itself); but does not support 120hz.
None of the 120hz LCDs currently out will convert 24p/fps/hz input to 120hz without first converting to 60hz and then doubling it to 120hz.
The Phillips and the Sharp D92u LCD TVs both first get the stream to 60hz and then double it to 120hz; I don't know about the Phillips but the Sharp uses Motion Interpolation Algorithms to perform the frame rate conversion from 60hz to 120. I also spent a considerable ammount of time working with Toshiba Tech support and getting escalated to a VP engineer to find out that their new LX177 series TV that will support 120hz also performs the same process (convert 24hz input to 60 via 3:2 pulldown, then FRC via Motion Interpolation to 120hz.)
-There's at least a couple of reasons for this:
1. It seems that it was determined that the #1 motion-related issue effecting LCDs (or at least the easiest to fix issue) was "retinal persistence". -It's the old "Stare at the american flag for 1 minute and then stare at the wall and your "minds eye" still sees the flag after you look away (with reverse colors, too). -Because LCD Displays show an image and hold it until the next image is sent to the screen, retinal persistence becomes an issue on these displays, it also makes motion more "jumpy" because an object will appear on the screen an stay where it is for a while until the next frame is displayed and then "jump" to the next point of motion. -Plasmas and CRTs don't have this issue as they "flash" the image on the screen briefly and then the image fades to black. Also, if you send the same image to a Plasma or CRT display twice the first frame will flash, fade, and then flash the second frame; if you send the same frame to an LCD TV twice in a row the display will not actually change when the second image is sent. -If your LCD is displaying 60hz content it is only being sent a new frame ever 16.7ms; the advertised response time doesn't really mean too much because the screen is only going to change once every 16.7ms anyway. When you move to a 120hz screen each frame is only show for 8.3ms before the next frame is displayed.
If an LCD TV's Video Processor were to actually accept a 24hz/fps/p signal and just take it "x5" like everyone keeps saying you WOULD have a 120hz signal but the 1st-5th frames and 6th-10th frames, etc.. would all be the same; again, when an LCD is sent the same frame that it's already displaying it doesn't change, so the display would only visibly change once every 24fps, which would make motion even worse. -The same thing would happen if an LCD took a 60hz signal and just doubled each frame to get to 120hz; this would cause the display to only physically change at 60hz. This is why the new 120hz LCDs are using Motion-Interpolation Algorithms to perform the frame-rate conversion from 60hz to 120hz; LCDs NEED new information every frame to actually refresh and increase perceived motion performance. The motion interpolation algorithms create a new frame of motion between each of the original frames so that new information is displayed at each cycle and the display is updated. -There are two side effects: 1 we have a slightly new cadence for our judder, and 2. Motion interpolation algorithms will display new wild and crazy artifacts when they fail to figure out certain complex motion scenarios. (Check out the Behardware review of the first samsung 100hz displays that came out in Europe that used Motion Interpolation Algorithms to convert 50hz pal to 100hz for some examples...)
I think the idea solution would be to have an LCD that supports both 60hz and 72hz refresh rates natively. (I don't know why LCD TVs all supposedly only support one refresh rate because my LCD computer monitor supports multiple refresh rates just fine.) Then when the LCD receives 24hz/p/fps content as an input it uses motion interpolation algorithms to generate TWO interpolated frames for every original frame (if the algorithms can do this with available processing power and without introducing too many artifcates) and then send the resulting 72hz frame to the display; the display would be running at 72hz (slightly better than 60hz), it wouldn't have any judder, and the display would be receiving a unique image every frame; each frame would be displayed for 13.8 ms.