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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
 

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Discussion Starter #22
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.
 

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Discussion Starter #24
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.
 

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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?
 

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Discussion Starter #26
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.
 

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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
 

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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
 

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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.
 

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Discussion Starter #30 (Edited)
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
 

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Discussion Starter #36 (Edited)
What color do you perceive is the center portion of these crossed objects?



The one on the left should look blue-ish. The one on the right should look yellow-ish. They are actually identical.

Go here for a demonstration of why they appear to be different:

https://www.echalk.co.uk/amusements/OpticalIllusions/colourPerception/colourPerception.html

Use the "mask opacity" slider feature with the illusion to variably desaturate the colored surrounds. Note that even when the surrounds are desaturated to the point of a pale pastel the effect still causes the center portions to appear different in color.

Here's the shocker- if a color analyser is focused on just the center portions, both readings will be identical, regardless of the color saturation of the surrounds . Your perception, however, will differ. This is the best demostration I have found that proves how vital it is to provide a truly neutral surround behind TVs and monitors.

Best regards and beautiful pictures,
G. Alan Brown, President
CinemaQuest, Inc.
SMPTE, Professional Video Alliance, THX, ISF, Lion AV Consultants
Twenty years of video viewing environment leadership and excellence in education and practical solutions
Developer of Ideal-Lume D65 bias lighting

"Advancing the art and science of electronic imaging"
 

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What color do you perceive is the center portion of these crossed objects?



The one on the left should look blue-ish. The one on the right should look yellow-ish. They are actually identical.

Go here for a demonstration of why they appear to be different:

https://www.echalk.co.uk/amusements/OpticalIllusions/colourPerception/colourPerception.html

Use the "mask opacity" slider feature with the illusion to variably desaturate the colored surrounds. Note that even when the surrounds are desaturated to the point of a pale pastel the effect still causes the center portions to appear different in color.

Here's the shocker- if a color analyser is focused on just the center portions, both readings will be identical, regardless of the color saturation of the surrounds . Your perception, however, will differ. This is the best demostration I have found that proves how vital it is to provide a truly neutral surround for TV installations.

Best regards and beautiful pictures,
G. Alan Brown, President
CinemaQuest, Inc.
SMPTE, Professional Video Alliance, THX, ISF, Lion AV Consultants
Twenty years of video viewing environment leadership and excellence in education and practical solutions
Developer of Ideal-Lume D65 bias lighting

"Advancing the art and science of electronic imaging"
Alan,
I'm curious: why should the wall opposite the display be dark? I always though "gray" for the wall BEHIND the display.
 

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Discussion Starter #38
Alan,
I'm curious: why should the wall opposite the display be dark? I always though "gray" for the wall BEHIND the display.
Many TVs have reflective screens. My plasma does and I plan to darken the opposite wall because I can faintly see sillouettes at times from objects/people between the TV and the opposite wall from the little that my bias lighting illuminates it.
 

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Alan,
I'm curious: why should the wall opposite the display be dark? I always though "gray" for the wall BEHIND the display.
The ideal is to have every wall you see from your seating position when you watch your display with neutral gray color, for the ultimate solution you need to paint with Munsell N5 calibrated paint which is neutral gray with flat spectral response, without having any hue bias because for the eye to see color accurately, the surround environment need to be chromatically neutral also.

Post-production studios have their room, even desks painted using a specific calibrated neutral gray paint.

There is an industry-specified neutral matte gray (vinyl latex emulsion) with 18% reflectance (Munsell N5) calibrated paint specifically formulated for critical color viewing conditions with neutral surround as specified by ISO 3664:2009 (Viewing Conditions - Graphic Technology & Photography) / SMPTE ST 2080-3:2017 (Reference Viewing Environment for Evaluation of HDTV Images), not all gray's are the same, you need spectrophotometric measurement to be sure that it has an equal mixture of all the spectrum (r-o-y-g-b-i-v) colors, for that reason that paint is multiple times more expensive and there only a few companies which are selling it.

Below is the calibration report of the Munsell N5 calibrated paint I use to my room for example:



To the opposite wall, its better to have black painted wall, blacks paint which is truly black is the Rosco TV black paint (which meets specifications for 3% reflectance), most of normal black paints have blue-ish tint.


You can use cloth also, where its ideal for projection rooms, the deepest back is called 'Triple Velvet Black', see there.





When you have Neutral Gray area behind your TV (or walls) where the D65 bias light will be reflecting, this will provide more comfort when you will watch movies because it stabilizes the irises. Also it provides a consistent white balance for your eyes, giving a constant reference in the peripheral area around your display, eliminating the negative effects of simultaneous contrast.

Also it will minimize the ''color pollution''of viewing area caused by reflections from chromatic surfaces.

When a high quality (Ideal-Lume PRO by CinemaQuest is great choice) D65 standard illumination is reflected from colored walls, etc., its color quality changes so it is no longer “standard”....but to use a D65 light, the walls have to be treated first, to minimize the 'color pollution' of viewing areas caused by reflections from chromatic surfaces.

The application of a neutral gray to chromatic surfaces will eliminate such color pollution by providing spectrally neutral surfaces around the viewing area.

Room light is critical for color grading rooms where they are working for many hours 8-14H a day to finish a project etc, see there: https://mixinglight.com/color-tutori...-suite-design/

How you will say WOW, all these stuff sound so crazy....has anyone that has done all these to his HT environment, yes..... Ted. lol
 

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The ideal is to have every wall you see from your seating position when you watch your display with neutral gray color, for the ultimate solution you need to paint with Munsell N5 calibrated paint which is neutral gray with flat spectral response, without having any hue bias because for the eye to see color accurately, the surround environment need to be chromatically neutral also.

Post-production studios have their room, even desks painted using a specific calibrated neutral gray paint.

There is an industry-specified neutral matte gray (vinyl latex emulsion) with 18% reflectance (Munsell N5) calibrated paint specifically formulated for critical color viewing conditions with neutral surround as specified by ISO 3664:2009 (Viewing Conditions - Graphic Technology & Photography) / SMPTE ST 2080-3:2017 (Reference Viewing Environment for Evaluation of HDTV Images), not all gray's are the same, you need spectrophotometric measurement to be sure that it has an equal mixture of all the spectrum (r-o-y-g-b-i-v) colors, for that reason that paint is multiple times more expensive and there only a few companies which are selling it.

Below is the calibration report of the Munsell N5 calibrated paint I use to my room for example:



To the opposite wall, its better to have black painted wall, blacks paint which is truly black is the Rosco TV black paint (which meets specifications for 3% reflectance), most of normal black paints have blue-ish tint.


You can use cloth also, where its ideal for projection rooms, the deepest back is called 'Triple Velvet Black', see there.





When you have Neutral Gray area behind your TV (or walls) where the D65 bias light will be reflecting, this will provide more comfort when you will watch movies because it stabilizes the irises. Also it provides a consistent white balance for your eyes, giving a constant reference in the peripheral area around your display, eliminating the negative effects of simultaneous contrast.

Also it will minimize the ''color pollution''of viewing area caused by reflections from chromatic surfaces.

When a high quality (Ideal-Lume PRO by CinemaQuest is great choice) D65 standard illumination is reflected from colored walls, etc., its color quality changes so it is no longer “standard”....but to use a D65 light, the walls have to be treated first, to minimize the 'color pollution' of viewing areas caused by reflections from chromatic surfaces.

The application of a neutral gray to chromatic surfaces will eliminate such color pollution by providing spectrally neutral surfaces around the viewing area.

Room light is critical for color grading rooms where they are working for many hours 8-14H a day to finish a project etc, see there: https://mixinglight.com/color-tutori...-suite-design/

How you will say WOW, all these stuff sound so crazy....has anyone that has done all these to his HT environment, yes..... Ted. lol
Ted & Alan,
Thank you for your explanations. My only problem with that ideal, no matter where I go, is WAF....sometimes I win, most times I lose!!!!! LOL
 
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