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Discussion Starter #1
Hi I'm Geezy and I'm new to the site and started this thread to intro myself and ask a few questions.


1. if blu-ray is supposed to have the highest picture quality how come the movies have grain like saw wich I'm watchin now.


I do know bit about all the tech but I'm here to learn from the ones who know it in and out.


2. what is PQ and AQ I see these letters a lot when I read threads. I think I have the answer but I want to be sure.


And go blu-ray..........
 

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Quote:
Originally Posted by geezy /forum/post/0


Hi I'm Geezy and I'm new to the site and started this thread to intro myself and ask a few questions.


1. if blu-ray is supposed to have the highest picture quality how come the movies have grain like saw wich I'm watchin now.


I do know bit about all the tech but I'm here to learn from the ones who know it in and out.


2. what is PQ and AQ I see these letters a lot when I read threads. I think I have the answer but I want to be sure.


And go blu-ray..........

The grain you are seeing is most likely what the director intended for. You will find plenty of "grainy" movies in both Blu-ray and HD-DVD. Sometimes it is however the product of an older film or poor transfer. I.E. - Field of Dreams or The Breakfast Club.


PQ = Picture Quality


AQ = Audio Quality


Welcome to AVS!!


~Josh
 

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Some movies just have more grain than others...There is some grain evident in some scenes in X-Men 3, but then in others it looks pristine.


Kingdom of Heaven also has a very clean picture in my opinion, and I hear Tears of the Sun is another good example of what Blu-Ray is capable of.
 

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Discussion Starter #4
thanx 4 the answers
 

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Film grain is generally too small to be encoded and seen on SD. HD has enough resolution to show almost all the film grain. This is why you are only now starting to notice it.
 

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What does this grain look like in HD? Does it look like noise? Tiny swarming blocks? If you pause the movie does it show as stationary tiny blocks?
 

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If you pause the movie does it show as stationary tiny blocks?

No, those are compression artifacts. Anything with a block is an artifact associated with compression. In some cases, these artifacts are even on the digital master.
 

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So, what does film grain look like in HD?

I'm trying to figure out if what I see in BD movies is film grain, noise or compression artifacts.
 

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Quote:
Originally Posted by WaldorfSalad /forum/post/0


So, what does film grain look like in HD?

I'm trying to figure out if what I see in BD movies is film grain, noise or compression artifacts.

you are seeing film grain and noise(noise can be from filming or added in post), compression artifacts are very hard to come by on either format


compression doesn't look like noise or film grain in the least



-Gary
 

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Guys to get rid of the "Grainy" effect you need to turn down your sets "Sharpness"! It is interfering with the BD natural details.
 

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Quote:
Originally Posted by Gary Murrell /forum/post/0


you are seeing film grain and noise(noise can be from filming or added in post), compression artifacts are very hard to come by on either format


compression doesn't look like noise or film grain in the least



-Gary

...to add, but both may be present at the same time and sometimes one will affect how the other one appears.


Film grain often looks like little, multi-colored specs/particles in the picture.


Electronic noise often looks like a thin layer of opaque whitish specs/particles.


Compression noise often has a block-like structure, where the blocks look like a blurred part of the image.


Going a little further...the "noise" can also occur as a result of the particular display. For instance, if you view an image and then pause it, if the noise is frozen in place, then that is suggesting the noise exists in the encoding of the actual program. If the noise still moves around while paused, that is suggesting it is a form of electronic noise that is being introduced by the display or the player. Alternately, this noise may stem from the particular kind of video postprocessing that is being done on the display or player.
 

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Quote:
Originally Posted by Smthkd /forum/post/0


Guys to get rid of the "Grainy" effect you need to turn down your sets "Sharpness"! It is interfering with the BD natural details.

I only partially agree with you. Excessive use of the "sharpness" control would obviously have an adverse effect on the picture quality, however even display devices that are poperly (ISF) calibrated (including proper adjustment of the "sharpness" control) the grain of certain BD titles is very noticeable.

I am one of the "lucky bastards" that are in posession of a NEC Theatersync (Silicon Optix Whitehorse) scaler
The "whitehorse" platform allows me to reduce the appearance of the "grain" quite significantly.
 

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Quote:
Originally Posted by Mr. Hanky /forum/post/0


Going a little further...the "noise" can also occur as a result of the particular display. For instance, if you view an image and then pause it, if the noise is frozen in place, then that is suggesting the noise exists in the encoding of the actual program. If the noise still moves around while paused, that is suggesting it is a form of electronic noise that is being introduced by the display or the player. Alternately, this noise may stem from the particular kind of video postprocessing that is being done on the display or player.

Great point, should be common sense but it may not occur to people to check.


thanks Mr. Hanky!
 

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William, great pics. They show what I get when I freeze scenes with grain/noise in the and is what I'm seeing in some scenes of BD discs and also in some HD programs from DirecTV or OTA. It looks like a bunch of moving dots. In each case if I pause the device (BD player or DirecTV HDTico receiver) the grain stops moving and looks like a lot of tiny blocks (much smaller than the blocks from compression artifacting). I often see this grain/noise in the sky of some scenes. An example is in the first chapter of Tears Of the Sun when the reporter is on the carrier deck and the sky is showing. The sky has that grain/moise. Also, in the briefing room when Tom Skerritt is shown against the wall. Also in a scene toward the end when the jets are coming in for the attack. Plus, in some scenes in Kingdom of Heaven when the sky is bluish.
 

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Quote:
Originally Posted by Gary Murrell /forum/post/0


you are seeing film grain and noise(noise can be from filming or added in post), compression artifacts are very hard to come by on either format


compression doesn't look like noise or film grain in the least



-Gary

I think I recognize compression artifacts. They are macroblocks, yes? Maybe my use of the term "tiny block" for frozen grain/noise was incorrect. The "tiny blocks" I see when freezing grain/noise are much, much smaller than macroblocks. They are probably close to dots but are larger than pixels. When not moving they can be confused with SSE (Silk Screen Effect) that is inherent in RP HDTVs.
 

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P.S. Is it safe to say that film grain looks the same as, and is as "bad"* in HD DVD movies as it is in Blu-ray movies?

*Ok, maybe describing film grain as "bad" is not the best word as some people apparently like it (I don't).
 

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You can avoid film grain by watching only movies that are done completely using digital HDCAM, the ones that mix film and HDCAM actually add grain in the HDCAM segments to make the look consistent, meaning they don't want segments that look different from other ones.


In the mean time, it is very hard to avoid. Unfortunately for film buffs and purists, the film grain does show through well on the HD disks, meaning this is something for the movie maker to think about in the future.


It is true that a bad compression job can make the grain much worse, so perhaps between filtering to minimize grain or compression artifacts, filtering is the lesser evil.


You can't really force moviemakers to avoid film just as you can't force the type of canvas or paint to use on an artist. My guess is that the whole thing would eventually be guided that direction by economics as well as ease of editing.


---

The moving noise that shows up in pause is typical of plasma on dark areas, but there are also display specific artifacts that come in from the scaler on these things on both LCDs and plasmas, and some of those show up even in motion.


There is another type of noise which I seem to be able to see more clearly than the banding that bugs others. It's the chroma noise in dark segments that seem to be from low light film, (it is very similar from a digital camera shots at low lighting --- ccd or cmos noise) this is different from grain behavour as it shows up as subtle changes in color in areas that are supposed to be solid. The problems show up in pause or motion and is everywhere I look.
 

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Quote:
P.S. Is it safe to say that film grain looks the same as, and is as "bad"* in HD DVD movies as it is in Blu-ray movies?

In some cases, a lot of grain is employed by the director to achieve a certain "look" to the film -- Miami Vice is a good example of that. In other cases, the degree to which grain is present may be unintentional -- the result of an unclean print.


Many say that the newer codecs like AVC and VC-1 are better equipped to handle grain from these "unclean prints." MPEG-2 tends to soften the picture in the presence of excess grain, particularly when sufficient video bandwidth (bitrate) isn't available -- i.e. with BD25.


On average, HD-DVDs probably exhibit a bit less grain, but the differences aren't nearly what they used to be. The past few months we've seen more and more Blu-ray titles released with cleaner transfers. Lately, we've also seen more titles released on BD50s with higher bitrates, which definitely helps to maintain a quality picture with MPEG-2 in the presence of grain.
 

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Quote:
In some cases, a lot of grain is employed by the director to achieve a certain "look" to the film -- Miami Vice is a good example of that.

It seemed to me that it was just overdone on Miami Vice. I got the HD-DVD release of it, and the mega-graininess was not what I look for in a hi-def title.
 
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