AVS Forum banner
Status
Not open for further replies.
1 - 8 of 8 Posts

·
Registered
Joined
·
203 Posts
Discussion Starter · #1 ·
I've logged about 100+ hours on my L300U LCD projector and I'm beginning to notice an unwelcomed consistency... the blurring of images when a movie scene pans horizontally across the screen. Is this a limitation of LCD technology, the L300U, my DVD player (Panny RP82) or the DVD format itself?
 

·
Registered
Joined
·
29 Posts
mvictorin, an interesting observation, I noticed it too with my AE-300 film.


As I test I tried a bit of Quake 3 via a HTPC and interestingly there was no blurring at all on that, compared to my 25ms respsonse time Samsung TFT monitor, so I can only really conclude that bradbissell is correct and the blur is actually the film :)


-- Jon
 

·
Registered
Joined
·
3,534 Posts
I see blurs on DLP projectors too. Could be DLP dither mixed with film blur that makes it more noticeable. Of course, watching an 84" screen does make it more obvious too, when you consider DVD's native resolution of 720x480. :)
 

·
Registered
Joined
·
406 Posts
I think it is a deinterlacing problem not LCD or DLP. The blur is alot of times is your progressive scan player kicking back to film mode and you get combing or feathering of the edges of moving objects. This will be very noticable on background objects. The edges of the object are feathered. It is my understanding that a pixel to pixel motion adaptive deinterlacer, which may cost a much as our machines, would greaty reduce this.


I notice this motion blur all the time. I have seen a couple machines do better jobs of reducing it. The best I have seen with DLP was on the new Marantz, other than that a CRT I viewed had a CS-1 box and it rarely had any motion blur.


Don't get me wrong there still will be blur because the speed of the original film vs. the speed of the panning of the camera, but with feathering it becomes very noticable.


BTW this happens of your regular RPTV as well but at smaller viewing angles it is less noticable.


--Don
 

·
Registered
Joined
·
454 Posts
I think it's DVD compression. Try freezing the image during motion. If it's still blurry, it's the DVD compression. I think the theory is that the human eye can't see that much detail when something is moving, so why bother encoding it on the DVD and wasting space. I don't think they meant for DVDs to be blown up to 100" diagonal or more.
 

·
Registered
Joined
·
1,260 Posts
I don't think anything. I KNOW :) that it is a limitation caused by the frame rate of the original film. I don't know if US tv's has this, but in Europe Philips has tv's with a feature called Digital Natural Motion on some 100 Hz tv's. This feature interpolates each field instead of just repeating them, creating 100 individually different interlaced fields per second. While this causes some digital artifacts (some will say heavy artifacts), it smooths out the picture to an incredible degree. Once you're used to it, anything else is stuttering, including the cinema. I personally notice it every time I go to the cinema, and every time I watch something without DNM. And since I don't own a DNM set, this is quite bothering... 24 fps simply isn't enough to create smooth pans. Personally I think a higher frame rate of the 70 mm shootings is the next step in increasing PQ, but this of course requires heavy investments of the cinemas...


But, in theory, wouldn't it be possible to shoot films in 120 fps? Then you could down-convert to 24 fps if necessary, without loosing anything compared to shooting 24fps in the first place, AND convert to 60P without 2-3 pulldown, resulting in a better PQ than with 24 fps originally.


Could anyone tell me, when HDTV is shot at 720P, is it really shot in 60 hertz progressive, or 30 hertz and then repeating each frame? How about HD D-vhs and stuff, do they contain 60P or 30P?
 

·
Registered
Joined
·
36 Posts
Most HiDef is just converted from film, so natively it is still 24fps. However, when it is shot on video then it is shot at 30fps. I'm not sure if 720p is actually shot at 60fps, but I doubt it. Seems as if the US industry is stuck at 24 or 30 fps. It is a hang up from the past.
 
1 - 8 of 8 Posts
Status
Not open for further replies.
Top