How Many Display Calibrators Ignore This? - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
 23Likes
Reply
 
Thread Tools
post #1 of 41 Old 08-06-2018, 11:13 AM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb How Many Display Calibrators Ignore This?

"The creation of television images that are intended to follow a standard of consistency in reproduction requires definition of a reference display, of a controlled viewing environment, and of a set of measurement procedures to enable consistent calibration of both display and environment. This document specifies a controlled viewing environment referred to as the Reference Viewing Environment." Introduction to: SMPTE ST 2080-3:2017 'Reference Viewing Environment for Evaluation of HDTV Images.'

Similar statements regarding a "reference viewing environment" being required appear consistently in the standards and recommended practices that define the benchmarks used by all video display calibration procedures. In other words, An otherwise "perfectly" calibrated display cannot deliver a reference image to the viewer in a non-reference environment.


Best regards and beautiful pictures,
G. Alan Brown, President
CinemaQuest, Inc.
SMPTE, Professional Video Alliance, THX, ISF, Lion AV Consutltants


"Advancing the art and science of electronic imaging"

Last edited by GeorgeAB; 12-02-2019 at 01:02 PM.
GeorgeAB is online now  
Sponsored Links
Advertisement
 
post #2 of 41 Old 08-06-2018, 11:20 AM
Advanced Member
 
Join Date: Jul 2017
Posts: 629
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 426 Post(s)
Liked: 212
I knew this already and I’m not a calibrator
GeorgeAB likes this.

Video: LG OLED 55 B7v | Calibration: i1D3 OEM, Calman Enthusiast.
Audio: Yamaha RX-V585, Polk s15e, Polk s10e, Polk s35ce, Atmos Dynavoice Magix FX-4, 2x Sub DIY Dayton RSS210HF Ported | Calibration: MiniDSP, UMIK-1, REW
MrRobotoPlus is offline  
post #3 of 41 Old 08-06-2018, 11:22 AM
AVS Forum Special Member
 
Join Date: Nov 2014
Location: College Station, Texas
Posts: 2,347
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 1133 Post(s)
Liked: 647
Quote:
Originally Posted by GeorgeAB View Post
"The creation of television images that are intended to follow a standard of consistency in reproduction requires definition of a reference display, of a controlled viewing environment, and of a set of measurement procedures to enable consistent calibration of both display and environment. This document specifies a controlled viewing environment referred to as the Reference Viewing Environment." Introduction to: SMPTE ST 2080-3:2017 'Reference Viewing Environment for Evaluation of HDTV Images.'

Similar statements regarding a "reference viewing environment" being required appear consistently in the standards and recommended practices that define the benchmarks used by all video display calibration procedures. In other words, An otherwise "perfectly" calibrated display cannot deliver a reference image to the viewer in a non-reference environment.


Best regards and beautiful pictures,
G. Alan Brown, President
CinemaQuest, Inc.
SMPTE, THX, ISF, Lion AV Consutltants


"Advancing the art and science of electronic imaging"
I think most calibrators ignore that because in most cases, save for a dedicated theater, tv viewing will almost never be in a reference environment, which I assume is a certain level of ambient light.
liffie420 is offline  
Sponsored Links
Advertisement
 
post #4 of 41 Old 08-06-2018, 11:46 AM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb

Quote:
Originally Posted by liffie420 View Post
I think most calibrators ignore that because in most cases, save for a dedicated theater, tv viewing will almost never be in a reference environment, which I assume is a certain level of ambient light.
You assumed erroneously, which is sort of the point. People wanting to adjust their display for a faithful reproduction of their favorite types of programs follow some kind of methodology. The point isn't the methodology, but what is really required to achieve their goal. Much is assumed, rather than getting the facts. Ambient light is only one of the many standards and recommendations.
GeorgeAB is online now  
post #5 of 41 Old 08-06-2018, 12:24 PM
AVS Forum Special Member
 
Join Date: Nov 2014
Location: College Station, Texas
Posts: 2,347
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 1133 Post(s)
Liked: 647
Quote:
Originally Posted by GeorgeAB View Post
You assumed erroneously, which is sort of the point. People wanting to adjust their display for a faithful reproduction of their favorite types of programs follow some kind of methodology. The point isn't the methodology, but what is really required to achieve their goal. Much is assumed, rather than getting the facts. Ambient light is only one of the many standards and recommendations.
Well that's the thing MAYBE %5 of people would go through the work to build a "reference room" I will be honest I don't even know what a reference room consists of. But the thing is most people just wont go through the effort, especially if it impacts the livability or usability of the room to achieve the reference. Not only that I think that at the same time probably better than half the people who buy tvs even bother to get their set calibrated in the first place, unless it is installed by say BestBuy or some other retailer and free calibration is offered. Generally I think most people if they can get a picture they like without going through the extra effort of finding a company to calibrate their display they will forgo it all together.
liffie420 is offline  
post #6 of 41 Old 08-06-2018, 12:38 PM
AVS Forum Addicted Member
 
Otto Pylot's Avatar
 
Join Date: May 2004
Location: Bull Mountain, OR
Posts: 15,851
Mentioned: 28 Post(s)
Tagged: 1 Thread(s)
Quoted: 3863 Post(s)
Liked: 2760
Quote:
Originally Posted by liffie420 View Post
Well that's the thing MAYBE %5 of people would go through the work to build a "reference room" I will be honest I don't even know what a reference room consists of. But the thing is most people just wont go through the effort, especially if it impacts the livability or usability of the room to achieve the reference. Not only that I think that at the same time probably better than half the people who buy tvs even bother to get their set calibrated in the first place, unless it is installed by say BestBuy or some other retailer and free calibration is offered. Generally I think most people if they can get a picture they like without going through the extra effort of finding a company to calibrate their display they will forgo it all together.
That is very true but most of the folks who come here are not your average tv viewer but someone who wants to get the best bang for their buck in not only the hardware but the proper setup. There is a reason why this forum is called the Audio Visual Science Forum. So I think that those who cruise these halls, while they may not be able to build a true home theater, want to do what they can to maximize their viewing experience. For example, bias lighting is great and relatively cheap way to improve pq, but if you don't know about the effects of other lighting in the room (windows for example), the color of the walls, room design, etc you won't get the desired effect unless you understand, or at least have a good working knowledge, of what is involved in a professional setup and then do what you can to fit that into your room scheme.

Understand the underlying science and then take away what will work best for you.
GeorgeAB likes this.
Otto Pylot is offline  
post #7 of 41 Old 08-06-2018, 01:48 PM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb

Quote:
Originally Posted by liffie420 View Post
Well that's the thing MAYBE %5 of people would go through the work to build a "reference room" I will be honest I don't even know what a reference room consists of. But the thing is most people just wont go through the effort, especially if it impacts the livability or usability of the room to achieve the reference. Not only that I think that at the same time probably better than half the people who buy tvs even bother to get their set calibrated in the first place, unless it is installed by say BestBuy or some other retailer and free calibration is offered. Generally I think most people if they can get a picture they like without going through the extra effort of finding a company to calibrate their display they will forgo it all together.
I am still surprised, after 21 years as an AV professional, how resistent participants in this 'Display Calibration' section of the forum are to viewing environment principles! These issues are not really so restrictive or constraining for home systems as you seem to fear. Most video consumers don't frequent this forum or have an interest in image fidelity. I don't post or advocate in 'People Magazine.' The point of teaching imaging science principles isn't just about reference performance. It's also about enabling video consumers to minimize unnecessary compromises. On this journey to understanding how video works, most wander aimlessly, or make it up as they go along, without a road map.
Plutotype likes this.
GeorgeAB is online now  
post #8 of 41 Old 08-06-2018, 01:59 PM
AVS Forum Special Member
 
Join Date: Nov 2014
Location: College Station, Texas
Posts: 2,347
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 1133 Post(s)
Liked: 647
Quote:
Originally Posted by GeorgeAB View Post
I am still surprised, after 21 years as an AV professional, how resistent participants in this 'Display Calibration' section of the forum are to viewing environment principles! These issues are not really so restrictive or constraining for home systems as you seem to fear. Most video consumers don't frequent this forum or have an interest in image fidelity. I don't post or advocate in 'People Magazine.' The point of teaching imaging science principles isn't just about reference performance. It's also about enabling video consumers to minimize unnecessary compromises. On this journey to understanding how video works, most wander aimlessly, or make it up as they go along, without a road map.
Don't get me wrong i do not disagree with you at all. And as I mentioned I have NO idea what even goes into making a room "reference". And again I also agree that most people on AVS are not average consumers either. FAR from it in most cases, only on AVS would 20 18" subwoofer be considered normal lol
GeorgeAB likes this.
liffie420 is offline  
post #9 of 41 Old 08-06-2018, 02:02 PM
Advanced Member
 
bryantc's Avatar
 
Join Date: Oct 2016
Location: Europa
Posts: 909
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 644 Post(s)
Liked: 596
The people making the content we watch don't even follow all of these rules. At some point you have to ask yourself how much is good enough.
mrtickleuk likes this.
bryantc is offline  
post #10 of 41 Old 08-06-2018, 02:21 PM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb

Quote:
Originally Posted by bryantc View Post
The people making the content we watch don't even follow all of these rules. At some point you have to ask yourself how much is good enough.
How do you know this? Only some of the people lack integrity. Your comment is a great example of the kind of stubborn reluctance I have seen for years. Why the nay-saying? A passion for excellence is indeed a rare thing in our world.



The best content producers do endeavor to maintain standards compliance! I know this as an insider, who communicates with these people fairly regularly. In any field of endeavor where humans are involved there will be no shortage of slackers.
GeorgeAB is online now  
post #11 of 41 Old 08-06-2018, 02:29 PM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Question

Quote:
Originally Posted by MrRobotoPlus View Post
I knew this already and I’m not a calibrator
Wait a minute......you own a color meter and CalMan software, but you don't calibrate video displays?
GeorgeAB is online now  
post #12 of 41 Old 08-06-2018, 02:58 PM
Advanced Member
 
bryantc's Avatar
 
Join Date: Oct 2016
Location: Europa
Posts: 909
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 644 Post(s)
Liked: 596
Quote:
Originally Posted by GeorgeAB View Post
How do you know this? Only some of the people lack integrity. Your comment is a great example of the kind of stubborn reluctance I have seen for years. Why the nay-saying? A passion for excellence is indeed a rare thing in our world.



The best content producers do endeavor to maintain standards compliance! I know this as an insider, who communicates with these people fairly regularly. In any field of endeavor where humans are involved there will be no shortage of slackers.
You should absolutely strive for the best but again at some point it is good enough.


There are people who spend more on cables than I did on my entire system. But when you go to a music studio you find out they are using the cheapest bulk cables they can buy. And when you open up your CD player it has a generic ribbon cable between boards.



My current home theater is in a completely dark room with dark brown (almost black) walls and carpet. I'm sure it doesn't meet any technical white paper specs but it is certainly good enough to let me enjoy the perfect blacks on my OLED.
mrtickleuk likes this.
bryantc is offline  
post #13 of 41 Old 08-06-2018, 04:10 PM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb

Quote:
Originally Posted by bryantc View Post
You should absolutely strive for the best but again at some point it is good enough.


There are people who spend more on cables than I did on my entire system. But when you go to a music studio you find out they are using the cheapest bulk cables they can buy. And when you open up your CD player it has a generic ribbon cable between boards.



My current home theater is in a completely dark room with dark brown (almost black) walls and carpet. I'm sure it doesn't meet any technical white paper specs but it is certainly good enough to let me enjoy the perfect blacks on my OLED.
Perhaps you missed my first question. How do you know "the people making the content we watch don't even follow all of these rules?"


How are you "sure it doesn't meet any technical white paper specs?"
GeorgeAB is online now  
post #14 of 41 Old 08-06-2018, 07:46 PM
AVS Forum Addicted Member
 
Otto Pylot's Avatar
 
Join Date: May 2004
Location: Bull Mountain, OR
Posts: 15,851
Mentioned: 28 Post(s)
Tagged: 1 Thread(s)
Quoted: 3863 Post(s)
Liked: 2760
Quote:
Originally Posted by bryantc View Post
There are people who spend more on cables than I did on my entire system. But when you go to a music studio you find out they are using the cheapest bulk cables they can buy. And when you open up your CD player it has a generic ribbon cable between boards.
That's because they bought into the fancy marketing and slick adverts without doing any serious research. As far as the music studios go, how many have you been in and seen generic, off-the-wall cables? Audio is a bit different than video.
GeorgeAB likes this.
Otto Pylot is offline  
post #15 of 41 Old 08-07-2018, 02:00 AM
AVS Forum Special Member
 
Light Illusion's Avatar
 
Join Date: Aug 2010
Posts: 1,980
Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Quoted: 874 Post(s)
Liked: 1355
We've been looking to add some info on this subject for a while.
A first draft of a page on Calibration & Viewing Environments can be seen here: https://www.lightillusion.com/viewing_environments.html
HDR will be added as soon as possible.

Steve
GeorgeAB and Otto Pylot like this.

Steve Shaw
LIGHT ILLUSION

Light Illusion is offline  
post #16 of 41 Old 08-07-2018, 09:25 AM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb

Quote:
Originally Posted by Light Illusion View Post
We've been looking to add some info on this subject for a while.
A first draft of a page on Calibration & Viewing Environments can be seen here: https://www.lightillusion.com/viewing_environments.html
HDR will be added as soon as possible.

Steve
Nicely done draft! This type of summary could be a benefit for folks who aren't inclined to invest in the expense and time to acquire various documents from the pertinent standards bodies for study. Such documents are copyright protected and only small portions can be directly quoted outside the document without permission.


I noted how the draft struggles with the home viewing environment issue. This, of course, is due to the limitless variety of compromises and conditions faced by an attempt to calibrate display performance in home environments. Certain compromises simply cannot be "calibrated away" and loss of picture quality and image fidelity unavoidably result. Rather than attempting to define all such compromises, I encourage serious videophiles to gain an understanding of the "Reference Viewing Environment" and emulate the standards and recommendations as close as possible.
GeorgeAB is online now  
post #17 of 41 Old 08-07-2018, 09:45 AM
AVS Forum Addicted Member
 
Otto Pylot's Avatar
 
Join Date: May 2004
Location: Bull Mountain, OR
Posts: 15,851
Mentioned: 28 Post(s)
Tagged: 1 Thread(s)
Quoted: 3863 Post(s)
Liked: 2760
Quote:
Originally Posted by Light Illusion View Post
We've been looking to add some info on this subject for a while.
A first draft of a page on Calibration & Viewing Environments can be seen here: https://www.lightillusion.com/viewing_environments.html
HDR will be added as soon as possible.

Steve
Nice summary! Other than the fact that "High" doesn't have a "t" at the end (Hight)
Otto Pylot is offline  
post #18 of 41 Old 08-07-2018, 09:59 AM
AVS Forum Special Member
 
Light Illusion's Avatar
 
Join Date: Aug 2010
Posts: 1,980
Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Quoted: 874 Post(s)
Liked: 1355
Quote:
Originally Posted by Otto Pylot View Post
Nice summary! Other than the fact that "High" doesn't have a "t" at the end (Hight)
Ooops!
Please feel free to spell-check the rest of the site too!

Edit to add: I can't find the spelling error?
Edited again: I found it!

Steve

Steve Shaw
LIGHT ILLUSION


Last edited by Light Illusion; 08-07-2018 at 10:06 AM.
Light Illusion is offline  
post #19 of 41 Old 08-07-2018, 10:09 AM
AVS Forum Addicted Member
 
Otto Pylot's Avatar
 
Join Date: May 2004
Location: Bull Mountain, OR
Posts: 15,851
Mentioned: 28 Post(s)
Tagged: 1 Thread(s)
Quoted: 3863 Post(s)
Liked: 2760
Quote:
Originally Posted by Light Illusion View Post
Ooops!
Please feel free to spell-check the rest of the site too!

Edit to add: I can't find the spelling error?
Edited again: I found it!

Steve
That just shows you that I did read your excellent summary.
GeorgeAB likes this.
Otto Pylot is offline  
post #20 of 41 Old 08-07-2018, 10:12 AM
AVS Forum Special Member
 
Light Illusion's Avatar
 
Join Date: Aug 2010
Posts: 1,980
Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Quoted: 874 Post(s)
Liked: 1355
I'm working on more info now...
Feel free to make any suggestion.

Steve

Steve Shaw
LIGHT ILLUSION

Light Illusion is offline  
post #21 of 41 Old 08-19-2018, 02:42 PM
Senior Member
 
Pio2001's Avatar
 
Join Date: Nov 2003
Location: France
Posts: 370
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 10
Hi,
I watch movies, videos, and surf the web on a calibrated 32" LCD monitor (Viewsonic VP3268-4K, IPS panel).
On the monitor, I have the choice between several presets, all calibrated at the factory (the monitor comes with its individual calibration report). The most useful ones being : sRGB (sRGB gamma), SMPTE-C (gamma 2.2), and rec709 (gamma 2.4).
For any of these presets, I can choose the overall brightness, but not the gamma.

For me, in everyday use, the most important factor that I must change according to the ambient light is the brightness of the screen. In the afternoom, the daylight enters the room, and I need a bright picture.
At night, the artificial light in the room is dimmer, and I need to decrease the brightness of the screen.

The second most important factor is the gamma curve. If the daylight enters the room, the gamma curves of 2.2 or 2.4 from the SMPTE-C and rec709 presets are too dark. I then switch to sRGB, whose gamma curve has brighter blacks, because of its linear part at the bottom of the greyscale.
But for movies, the sRGB gamma curve gives a picture that lacks dynamics. It is better to darken the room and choose one of the two other gamma options.

I switch between SMPTE-C and rec709 mostly because of their different gamma curves. The difference in colours is minimal in comparison.

Eventually, I use mostly 4 presets :
Daylight, web and Youtube : sRGB
Dark room, web : custom preset with very low brightness (brightness = 0 and gain below 100%)
Dark room, bright movies : rec-709
Dark room, dark movies : SMPTE-C

Pio2001
Pio2001 is offline  
post #22 of 41 Old 08-19-2018, 03:52 PM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb

Quote:
Originally Posted by Pio2001 View Post
Hi,
I watch movies, videos, and surf the web on a calibrated 32" LCD monitor (Viewsonic VP3268-4K, IPS panel).
On the monitor, I have the choice between several presets, all calibrated at the factory (the monitor comes with its individual calibration report). The most useful ones being : sRGB (sRGB gamma), SMPTE-C (gamma 2.2), and rec709 (gamma 2.4).
For any of these presets, I can choose the overall brightness, but not the gamma.

For me, in everyday use, the most important factor that I must change according to the ambient light is the brightness of the screen. In the afternoom, the daylight enters the room, and I need a bright picture.
At night, the artificial light in the room is dimmer, and I need to decrease the brightness of the screen.

The second most important factor is the gamma curve. If the daylight enters the room, the gamma curves of 2.2 or 2.4 from the SMPTE-C and rec709 presets are too dark. I then switch to sRGB, whose gamma curve has brighter blacks, because of its linear part at the bottom of the greyscale.
But for movies, the sRGB gamma curve gives a picture that lacks dynamics. It is better to darken the room and choose one of the two other gamma options.

I switch between SMPTE-C and rec709 mostly because of their different gamma curves. The difference in colours is minimal in comparison.

Eventually, I use mostly 4 presets :
Daylight, web and Youtube : sRGB
Dark room, web : custom preset with very low brightness (brightness = 0 and gain below 100%)
Dark room, bright movies : rec-709
Dark room, dark movies : SMPTE-C
Video industry standards and recommended practice regarding gamma and EOTF must always be understood to be in a "reference viewing environment." Your personal observations and practice may help guide certain viewers in similarly compromised viewing conditions to achieve a more personally pleasing experience. Other people may disagree with your methodology and have their own. That's the point of standards to begin with. Image fidelity, consistent repeatability, and accurate reproduction of video programs for the majority of human viewers are objectives not available otherwise. As a mass-communication medium, video program reproduction relies on systemized standards to preserve artistic expression and unified performance.
GeorgeAB is online now  
post #23 of 41 Old 08-21-2018, 02:55 AM
aka jfinnie
 
Join Date: Aug 2015
Location: Norwich, UK
Posts: 3,959
Mentioned: 78 Post(s)
Tagged: 0 Thread(s)
Quoted: 3191 Post(s)
Liked: 2326
While I care a lot about calibrating my projection system which is in a dedicated room, I care very little about my TV which is in an extremely compromised lounge.
Are there any similar specifications for reference standard projection?
bobof is online now  
post #24 of 41 Old 08-21-2018, 08:43 AM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb

Quote:
Originally Posted by bobof View Post
While I care a lot about calibrating my projection system which is in a dedicated room, I care very little about my TV which is in an extremely compromised lounge.
Are there any similar specifications for reference standard projection?
The current industry reference for projected motion images is the Digital Cinema Initiative (DCI) specifications. They were adapted from pre-existing SMPTE cinema standards and recommended practices when digital cinema started replacing film projection in commercial cinemas. Those specs must be adjusted and adapted to accommodate video format differences and limitations when displaying video programs.

Certain parts of the DCI spec. relate to viewing environment issues, as did the specs for film exhibition. How much ambient light reflecting off of the screen is much more easily controlled in a residential application, since walkpath lighting and illuminated exit signs are not required by safety and fire regulations. The white point of tolerated ambient light for video projection is the same as for televisions. Ambient light level should be reduced to the barest minimum. Eye strain is not a concern due to the reduced level of peak screen brightness. That may change with HDR and evolving technology, such as with direct-view, micro-LED screens, etc.
GeorgeAB is online now  
post #25 of 41 Old 08-21-2018, 02:53 PM
aka jfinnie
 
Join Date: Aug 2015
Location: Norwich, UK
Posts: 3,959
Mentioned: 78 Post(s)
Tagged: 0 Thread(s)
Quoted: 3191 Post(s)
Liked: 2326
Quote:
Originally Posted by GeorgeAB View Post
The current industry reference for projected motion images is the Digital Cinema Initiative (DCI) specifications. They were adapted from pre-existing SMPTE cinema standards and recommended practices when digital cinema started replacing film projection in commercial cinemas. Those specs must be adjusted and adapted to accommodate video format differences and limitations when displaying video programs.

Certain parts of the DCI spec. relate to viewing environment issues, as did the specs for film exhibition. How much ambient light reflecting off of the screen is much more easily controlled in a residential application, since walkpath lighting and illuminated exit signs are not required by safety and fire regulations. The white point of tolerated ambient light for video projection is the same as for televisions. Ambient light level should be reduced to the barest minimum. Eye strain is not a concern due to the reduced level of peak screen brightness. That may change with HDR and evolving technology, such as with direct-view, micro-LED screens, etc.
Unless I'm missing something, all the potentially useful information has been removed from the latest V1.3 of the DCI specifications.
There was a section in V1.2 that had some useful info.
I say "some" because I'm not sure even how applicable it is to a home system.

As you say, in the home system it is possible to much more tightly control the environment. Plus the projectors can be much better specified than even the mastering projector discussed for DCI (2000:1 contrast / 2.6gamma / 48 nit peak white).

Which leads to an interesting question when we're talking about comparing to the reference system that the movie was mastered on. If the reference display did indeed have 2000:1 contrast and peak white at 48 nits; then my home system set for 2.4 gamma with the same white point is going to have much, much darker response down at the 0-3% levels. If the peak white is the same, then doesn't this make it harder to discern the detail in dark sections with mixed APL...

I'm really puzzling on how you would configure your projection system if you really want to see it as it was envisaged by the director, and not just with very dark blacks because that is what the projector happens to be capable of.

So what is the best practice with a projector whose contrast ratio is many, many times greater than that of the specified mastering projector?
bobof is online now  
post #26 of 41 Old 08-21-2018, 07:59 PM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb

You cannot fully equate consumer video with either DCI, or Dolby Cinema, or professional video at 12 bits, cinema white point, P3 color, EOTF, etc. Consumer video is an adaptation of professional cinema formats. Some directors and cinematographers oversee and approve consumer video conversion masters, others leave it up to post-production technicians they have confidence in based upon past work, reputation, etc.
GeorgeAB is online now  
post #27 of 41 Old 08-22-2018, 02:16 AM
aka jfinnie
 
Join Date: Aug 2015
Location: Norwich, UK
Posts: 3,959
Mentioned: 78 Post(s)
Tagged: 0 Thread(s)
Quoted: 3191 Post(s)
Liked: 2326
Quote:
Originally Posted by GeorgeAB View Post
You cannot fully equate consumer video with either DCI, or Dolby Cinema, or professional video at 12 bits, cinema white point, P3 color, EOTF, etc. Consumer video is an adaptation of professional cinema formats. Some directors and cinematographers oversee and approve consumer video conversion masters, others leave it up to post-production technicians they have confidence in based upon past work, reputation, etc.
Sure, that much is a given, and hence my original question, which the spec you suggest barely addresses (and certainly not for the home, or usefully for high contrast projectors which have been available for the last ~10 years...)

is the answer to my original question - no, there aren't applicable reference standards for projection viewing environment in the home? Or yes, they do exist, but it isn't this spec? It's this A.N. other spec?

What I'm looking for is hard science and standards based information on how a high native contrast projector and the environment it is in should be set up in order to get a "reference" quality image. So far I can't actually find anything.

My thought process and reason for my queries is this:

Many of these projectors achieve blacks lower than even the CRT reference monitors traditionally used (I see <0.001 nits in my room black floor off the screen without resorting to dynamic dimming; info in Dolby's Pulsar monitor white paper suggests black on a Pulsar or CRT reference is around 0.005 nits). There are huge threads on here about home theatres striving to be as black as possible for projection - which actually further increases the delta to the "reference" viewing environment discussed for the way the content is mastered for home viewing.

Now I'm not going to lie - my room when calibrated to REC709/2.4 gamma, 56nit peak white, <0.001 nit black, no background light results in a very pleasing, extremely contrasty image with plenty of detail. Any outsider who views it is awestruck that such an image is available at this size in a home. But I'm left dissatisfied - I have all the gear and software as used by professionals, and the ability to calibrate it to whatever standard I'd like... except they don't seem to exist for home projection!

In particular the area I long to be able to "know" is correct is the display of the lowest levels (1-5%) which is exactly where the room environment and native contrast of the display have the biggest effect.
bobof is online now  
post #28 of 41 Old 08-22-2018, 03:38 AM
AVS Forum Special Member
 
Light Illusion's Avatar
 
Join Date: Aug 2010
Posts: 1,980
Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Quoted: 874 Post(s)
Liked: 1355
No, there is no 'specification' for a projection based viewing, or grading, environment.

With grading environments they are basically 'black, non-reflective' rooms.
The only lighting is often that illuminating the grading control surface.
(We have build a lot of projection based grading environments over the years.)

With the final consumer theatre projection environment there are far more issues, due to poor colour/finish of seating/walls/floor/ceiling, and the inevitable, and legally required, safety lighting, including the (normally) green Exit signs.

For a home projection environment, you will want to best match the grading room.

Steve
bobof and GeorgeAB like this.

Steve Shaw
LIGHT ILLUSION


Last edited by Light Illusion; 08-22-2018 at 03:43 AM.
Light Illusion is offline  
post #29 of 41 Old 08-22-2018, 07:54 AM
Advanced Member
 
Join Date: Jul 2017
Posts: 629
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 426 Post(s)
Liked: 212
Quote:
Originally Posted by GeorgeAB View Post
Wait a minute......you own a color meter and CalMan software, but you don't calibrate video displays?
yes, i do, but i'm not a PRO calibrator.

Video: LG OLED 55 B7v | Calibration: i1D3 OEM, Calman Enthusiast.
Audio: Yamaha RX-V585, Polk s15e, Polk s10e, Polk s35ce, Atmos Dynavoice Magix FX-4, 2x Sub DIY Dayton RSS210HF Ported | Calibration: MiniDSP, UMIK-1, REW
MrRobotoPlus is offline  
post #30 of 41 Old 08-22-2018, 10:35 AM - Thread Starter
AVS Forum Special Member
 
GeorgeAB's Avatar
 
Join Date: Feb 2002
Location: Denver, CO metro area, www.cinemaquestinc.com
Posts: 3,837
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 247 Post(s)
Liked: 348
Lightbulb

Quote:
Originally Posted by bobof View Post
Sure, that much is a given, and hence my original question, which the spec you suggest barely addresses (and certainly not for the home, or usefully for high contrast projectors which have been available for the last ~10 years...)

is the answer to my original question - no, there aren't applicable reference standards for projection viewing environment in the home? Or yes, they do exist, but it isn't this spec? It's this A.N. other spec?

What I'm looking for is hard science and standards based information on how a high native contrast projector and the environment it is in should be set up in order to get a "reference" quality image. So far I can't actually find anything.

My thought process and reason for my queries is this:

Many of these projectors achieve blacks lower than even the CRT reference monitors traditionally used (I see <0.001 nits in my room black floor off the screen without resorting to dynamic dimming; info in Dolby's Pulsar monitor white paper suggests black on a Pulsar or CRT reference is around 0.005 nits). There are huge threads on here about home theatres striving to be as black as possible for projection - which actually further increases the delta to the "reference" viewing environment discussed for the way the content is mastered for home viewing.

Now I'm not going to lie - my room when calibrated to REC709/2.4 gamma, 56nit peak white, <0.001 nit black, no background light results in a very pleasing, extremely contrasty image with plenty of detail. Any outsider who views it is awestruck that such an image is available at this size in a home. But I'm left dissatisfied - I have all the gear and software as used by professionals, and the ability to calibrate it to whatever standard I'd like... except they don't seem to exist for home projection!

In particular the area I long to be able to "know" is correct is the display of the lowest levels (1-5%) which is exactly where the room environment and native contrast of the display have the biggest effect.
.
As far as I know, the standards bodies have not defined specs for residential projection systems. CEDIA, THX, ISF, CEA, and perhaps others have published guidelines for residential projection theaters but none of those organizations are motion imaging industry standards bodies. They do what I alluded to earlier and adapt professional standards, engineering guidelines and recommended practices to the consumer market and residential systems industry. Most of the fundamental principles apply across the board. It's also ok to exceed certain specs, such as black level.


Best regards and beautiful pictures,
G. Alan Brown, President
CinemaQuest, Inc.
SMPTE, Professional Video Alliance, THX, ISF, Lion AV Consultants


"Advancing the art and science of electronic imaging"
bobof likes this.

Last edited by GeorgeAB; 12-02-2019 at 01:22 PM.
GeorgeAB is online now  
Sponsored Links
Advertisement
 
Reply Display Calibration

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off