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Discussion Starter · #1 ·
This mostly relates to film. If I am watching a movie (from Dish or BD), and there is a scene which appears blurry (in motion), if I freeze a frame and the frozen frame is appears blurry, is it safe to say that the artifact is in the source and not the display? Does the same test apply for other motion artifacts like ghosting, smearing, trailing, etc. (i.e. if frozen frame exhibit the same problem then it is the source??)


What about judder, is there a equivalent test? If I am outputting 1080p/24fps from my BD player and my TV indicates 24Hz and I still see some judder is it safe to say that the judder is due to 24fps film signal since I am not doing 3:2 pulldown?


Please help!
 

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Wow, I'm surprised no one has answered this.


Yes, thats a legit test for motion blur. If the blur is frozen with the pause, its in the source. If the blur was caused by the tv, it would instantly snap into focus when you paused it much the same way that motion blur is evident on an object when the camera is panning then they snap back into crystal clear sharpness when the camera stops moving.


Pretty much on all but the most inexpensive of LCD displays for the last couple of generations, 90% of any motion blur you see is in the source or caused by bad compression from Cable/Satellite feeds or poorly compressed DVD movies (most good quality movies on DVD9 won't have this issue). You should almost never encounter such issues with Blu Ray.

Quote:
What about judder, is there a equivalent test? If I am outputting 1080p/24fps from my BD player and my TV indicates 24Hz and I still see some judder is it safe to say that the judder is due to 24fps film signal since I am not doing 3:2 pulldown?

Absolutely correct. 24 fps is inherently "jittery". Most of the good quality HDTV's have processing that get rid of it or lessen it considerably (running it at 48hz etc) but you may still notice some when runing native 24p from a BD. I haven't noticed any Judder on my 60hz Sammy yet and I run all my BD's at 24p if possible.
 

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Yeah. when you watch a Blu-ray in pure 24p mode, judder inherent in the 24fps photography becomes painfully obvious, and more evident than in the movie theater. Double shuttering projectors used in theaters mask much of the judder, but to minimize it in the HT context you have to resort to some processing tricks.
 

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Discussion Starter · #4 ·

Quote:
Originally Posted by NuSoardGraphite /forum/post/18174796


Wow, I'm surprised no one has answered this.


Yes, thats a legit test for motion blur. If the blur is frozen with the pause, its in the source. If the blur was caused by the tv, it would instantly snap into focus when you paused it much the same way that motion blur is evident on an object when the camera is panning then they snap back into crystal clear sharpness when the camera stops moving.


Pretty much on all but the most inexpensive of LCD displays for the last couple of generations, 90% of any motion blur you see is in the source or the cause of bad compression from Cable/Satellite feeds or poorly compressed DVD movies (most good quality movies on DVD9 won't have this issue). You should almost never encounter such issues with Blu Ray.




Absolutely correct. 24 fps is inherently "jittery". Most of the good quality HDTV's have processing that get rid of it or lessen it considerably (running it at 48hz etc) but you may still notice some when runing native 24p from a BD. I haven't noticed any Judder on my 60hz Sammy yet and I run all my BD's at 24p if possible.

Thanks man! That is the confirmation I was looking for.
 

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Quote:
Originally Posted by JohnFR /forum/post/18175410


Double shuttering projectors used in theaters mask much of the judder, .....

Isn't it contrary to the director's intent as much as frame interpolation? We read a lot how 24fps is used deliberately to make movies look like movies.
 

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Quote:
Originally Posted by ramazur /forum/post/18195647


Isn't it contrary to the director's intent as much as frame interpolation? We read a lot how 24fps is used deliberately to make movies look like movies.

No, it's still 24fps but the double shuttering projectors reduces the apparent judder somewhat. The directors are largely stuck with 24fps because it is industry standard going back to Edison, unless they are shooting in digital or on film at a higher frame rate. Double shuttering film projectors merely mask judder but in no way alter the source material, unlike the various types of digital processing that goes on within HDTV's.
 

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Quote:
Originally Posted by JohnFR /forum/post/18201253


No, it's still 24fps but the double shuttering projectors reduces the apparent judder somewhat. The directors are largely stuck with 24fps because it is industry standard going back to Edison, unless they are shooting in digital or on film at a higher frame rate. Double shuttering film projectors merely mask judder but in no way alter the source material, unlike the various types of digital processing that goes on within HDTV's.

They are not "stuck" with 24fps. It is the director's choice of frame rate. A lot of old-school directors are still very hard-headed and stuck wiith the idea that 24fps gives a "film-like" dreamy state quality to their works. The truth, is that 24fps was chosen because it was the MINIMUM speed required to represent a somewhat life-like motion back in the old days of film. Upping the frame rate would have meant more film canisters being shipped to each theater, increasing costs.


There is no reason these days to stick with 24fps, except for "artistic" purposes. It's still amazing though, that a lot of directors and the industry in general, is so hard-headed that they don't create a new higher frame rate standard. 24fps has never been enough to represent life-like motion.


There have been attempts at increasing the frame rate standard. Maxivision 48fps was one that never took off. It's amazing that a format like Maxivison or Todd-AO from the 1950's wasn't more successful. It is amazing seeing something in this film format. (70mm, at 30fps). Much smoother frame rate and higher resolution.
 

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Quote:
Originally Posted by Dathon /forum/post/18214432


They are not "stuck" with 24fps. It is the director's choice of frame rate. A lot of old-school directors are still very hard-headed and stuck wiith the idea that 24fps gives a "film-like" dreamy state quality to their works. The truth, is that 24fps was chosen because it was the MINIMUM speed required to represent a somewhat life-like motion back in the old days of film. Upping the frame rate would have meant more film canisters being shipped to each theater, increasing costs.


There is no reason these days to stick with 24fps, except for "artistic" purposes. It's still amazing though, that a lot of directors and the industry in general, is so hard-headed that they don't create a new higher frame rate standard. 24fps has never been enough to represent life-like motion.


There have been attempts at increasing the frame rate standard. Maxivision 48fps was one that never took off. It's amazing that a format like Maxivison or Todd-AO from the 1950's wasn't more successful. It is amazing seeing something in this film format. (70mm, at 30fps). Much smoother frame rate and higher resolution.

So true. I can only hope that 3D set will help with transit from this terrible old frame rate to at least 60FPS.

For years I suffered from what I tough LCD motion blur, and when I finally got Panasonic plasma I was shocked to see all the same song and dance again.


I now understand why NBC 1080i/60 stream, and the video games in 60FPS only look good on my plasma. In contrast all that old technology and people that utilize it makes me sick every time I see any even slightest motion on screen. What people do not understand is that 120Hz or 240Hz TV sets are just try to cure what was wrong from the beginning - source.

I do not care if directors want to introduce "dreamy" quality that only make my new tv showing blurry juddery mess. The same thing with the games under 60FPS, horrible.

But thenology is changinng and all "dreamers" will have to fallow eventualy.

3D set could be exactly what we needed to brings us from dark ages of TV.
 

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Quote:
Originally Posted by dukic /forum/post/18215306


So true. I can only hope that 3D set will help with transit from this terrible old frame rate to at least 60FPS.

For years I suffered from what I tough LCD motion blur, and when I finally got Panasonic plasma I was shocked to see all the same song and dance again.


I now understand why NBC 1080i/60 stream, and the video games in 60FPS only look good on my plasma. In contrast all that old technology and people that utilize it makes me sick every time I see any even slightest motion on screen. What people do not understand is that 120Hz or 240Hz TV sets are just try to cure what was wrong from the beginning - source.

I do not care if directors want to introduce "dreamy" quality that only make my new tv showing blurry juddery mess. The same thing with the games under 60FPS, horrible.

But thenology is changinng and all "dreamers" will have to fallow eventualy.

3D set could be exactly what we needed to brings us from dark ages of TV.

Great post. If the "art" of 24fps gives me pain, and it does, the "art" goes as does the so-called "director's intent". The same for the shaky-hand camera.
 

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The cause of blur has nothing to do with frame rate. Blur is added to eliminate/reduce perceivable motion judder.


The majority of movies are filmed in 24p with shutter speed of 48.1


Below is a quote from one of my ealier posts


"There is a fine line between blur and motion detail (akin to flicker and blur). When capturing or rendering motion in low frame-rate, blur is applied to reduce the appearance of motion judder (where motion is perceived as series of still images...double images if you will). It is causes by prolonged frame latency and although applying blur reduces motion detail, but it helps to fool our eyes into believing the motion is continues. In other words, it helps to aid the transition between the frames.


Film directors induce blur by capping the shutter speed to 48 or less and game developers apply artificial blur to induce smooth look (UE3 is an excellent example).



In order to for us (humans) to view lossless motion with no detectable latency, the frame-rate has to be above 300fps. Unfortunately, it can cause 'artificial look' it's not worth the extra bandwidth/storage space and processing."




There are some excellent view samples on the link below

http://www.avsforum.com/avs-vb/showt...482&highlight=

http://www.avforums.com/forums/plasm...-judder-2.html

http://www.avforums.com/forums/plasm...ages-bd-5.html


http://www.avforums.com/forums/11279753-post88.html
 

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Quote:
Originally Posted by dandaroy /forum/post/18170732


What about judder, is there a equivalent test? If I am outputting 1080p/24fps from my BD player and my TV indicates 24Hz and I still see some judder is it safe to say that the judder is due to 24fps film signal since I am not doing 3:2 pulldown?


Please help!

Telecine Judder is caused by uneven pull-down (e.g. 2:3). Low-motion judder is caused by low frame-rates (e.g. 24p) where there's isn't enough samples to create continuousness free-flowing effect.


This is where low-level MCFI comes in. If don't like the look of raw 24p, you can up-samples it to higher frame rates. But thus far, only few manufactures have managed to prefect the algorithm to an acceptable level (Panasonic, Toshiba and Philips).
 
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