The Future of Cinema - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 19 Old 04-21-2017, 03:15 PM - Thread Starter
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The Future of Cinema

Video guru Joe Kane talks about what he saw and learned at CinemaCon 2017, the trade show for commercial-cinema owners. Topics include the lengths to which theater owners will go to attract customers, such as augmented-reality lobby posters, first-class airline seating with meal and drink service in theaters, and the Barco Escape three-screen system. He also discusses the potential of direct-LED screen walls such as the Sony CLEDIS and Samsung Cinema Screen, the importance of bias lighting even with projectors, high dynamic range, answers to chat-room questions, and more.

https://www.avsforum.com/the-future-of-cinema/
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post #2 of 19 Old 04-21-2017, 11:16 PM
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I wonder if modern viewers would give the same results as Joe's study of eye fatigue. I know that when I first started getting into AV back in the early 90s, I used to feel eye strain/visual fatigue often. But now that I spend so much more time in front of a screen, I don't feel it hardly at all...
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post #3 of 19 Old 04-22-2017, 04:12 PM
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I'm not sure I like the direction it's going in. Bouncing sound of the big screen..come on. No way you'd get any sort of descent imaging doing it that way. There has to be a way of getting some kind of HDR with multiple laser projectors. The LED walls are super expensive as well. Couldn't you somehow stack like 6 laser projectors and get crazy brightness?

The obvious fix that would make me go back to theaters is to be one generation ahead. As it is now they are one generation behind what I have at home. Give me 8k with HDR 120Hz and a crazy soundsystem that I couldn't possibly install at home. 12 x 24" subs etc. They need to step up their game big time! Local theaters here have uncalibrated 2k image and speakers that are driven way beyond their capacity so they distort. I bet there are some nice theaters in CA but at most places that's where it's at. First class seating etc. is nice but I want the picture and sound to blow me away and not look and sound worse than my amateur theater at home.
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post #4 of 19 Old 04-23-2017, 12:56 PM
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I wonder if modern viewers would give the same results as Joe's study of eye fatigue. I know that when I first started getting into AV back in the early 90s, I used to feel eye strain/visual fatigue often. But now that I spend so much more time in front of a screen, I don't feel it hardly at all...
The Society of Motion Picture and Television Engineers (SMPTE) has a current research committee working on revising human factors standards and recommended practices for HDR cinema, post production, broadcast, and home environments. Joe Kane was the chair of the professional monitor working group that developed SMPTE's previous publication pertaining to this topic.

Our eyesight changes gradually as we age. No two individuals have identical sensitivity when it comes to perception. However, the human factor studies Joe refers to incorporate a relatively wide sampling of types of viewers. The resulting recommendations are offered to approximate an "average" viewer's needs. It must be kept in mind that the fundamental basis of these studies is how humans respond to constantly fluctuating levels of emitted and reflected light in a darkened environment.

In addition to iris activity, as Joe described, another fatigue-inducing element in the human visual system is brightness adaptation. There are multiple parts of this that occur in the physical optical system and brain when ambient conditions change from dark to light. The retina has electrical and chemical processes that can take up to about a half hour to fully adapt to a very dark environment. Fatigue is typically induced in most viewers when very dark to very bright shifts occur in random sequence throughout many programs. This is quite common when TV shows are edited to stimulate interest, or when commercials are inserted into broadcast programs.

A great experiment for the average viewer is to turn the sound off, plus the room lights off while watching a typical broadcast TV show at night. Turn your back to the TV and observe how much the light reflected in the room changes in brightness, plus how frequently and erratically it occurs. This effect is somewhat comparable to driving on an interstate highway late at night toward oncoming vehicle headlights, a notoriously fatiguing activity.

Many other of Joe's comments pertaining to viewing environment conditions focus upon various ways room design can negatively affect the audience experience. This technical paper is the result of studying Joe's writings, among many others, then endeavoring to summarize and demonstrate key practical principles: "The Importance of Viewing Environment Conditions in a Reference Display System."

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SMPTE, THX, ISF, Lion AV Consultants

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post #5 of 19 Old 04-23-2017, 01:32 PM
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I'm not sure I like the direction it's going in. Bouncing sound of the big screen..come on. No way you'd get any sort of decent imaging doing it that way. There has to be a way of getting some kind of HDR with multiple laser projectors. The LED walls are super expensive as well. Couldn't you somehow stack like 6 laser projectors and get crazy brightness?

The obvious fix that would make me go back to theaters is to be one generation ahead. As it is now they are one generation behind what I have at home. Give me 8k with HDR 120Hz and a crazy sound system that I couldn't possibly install at home. 12 x 24" subs etc. They need to step up their game big time! Local theaters here have uncalibrated 2k image and speakers that are driven way beyond their capacity so they distort. I bet there are some nice theaters in CA but at most places that's where it's at. First class seating etc. is nice but I want the picture and sound to blow me away and not look and sound worse than my amateur theater at home.
It is sad that there are still so many commercial cinema venues around the world with seriously compromised presentations. However, I believe that most movie fans cannot afford to have a home system performance that can rival the average digital cinema experience. What you enjoy in your home sounds like it is exceptional, even among this forum community.

I still enjoy attending commercial cinemas on a fairly regular basis. This is in spite of the fact that I have a dedicated projection home cinema with a Joe Kane designed 1080p projector, a JKP designed 2.35:1 screen, comprehensive light control, acoustic treatments, and 7.1 channel (w/2 subs) THX Select surround system. I am grateful to live in the Denver Metro area, where we have a Dolby Cinema certified venue (soon to be another two), multiple IMAX theaters, plus several Dolby Atmos equipped auditoriums around town.
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post #6 of 19 Old 04-24-2017, 05:23 PM
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Scott, good article. I was happy/interested in the talk of Ambient Lighting[ behind the display] and the effect on HDR. I have AL behind my plasma it differently happy w/ PQ. I was concerned about, if HDR was a great value to me on my new display coming soon & which way to go[FALD LED or OLED]. I like the effects on AL on my current setup and feel a little better that AL will not wash out the effects of HDR. They just have to be calibrated together.
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post #7 of 19 Old 04-26-2017, 10:56 AM
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I was intrigued by the bias lighting for projectors. I have a modest HT set up as part of a great room. While I have good light control, I do have a white ceiling.

If I take the area of my 120" screen and Epson 3500's lumens in Natural, I think I am right around 50ft L (I have a grey screen with 1.0 gain). I think this is right around where I should be in a room with some ambient light (reflection from ceiling).

Is it worth trying bias lighting in my situation? My blacks aren't terrific to begin with...useable, but not great. I am sure the white ceiling doesn't help. Thanks!
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post #8 of 19 Old 04-26-2017, 12:04 PM
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I was intrigued by the bias lighting for projectors. I have a modest HT set up as part of a great room. While I have good light control, I do have a white ceiling.

If I take the area of my 120" screen and Epson 3500's lumens in Natural, I think I am right around 50ft L (I have a grey screen with 1.0 gain). I think this is right around where I should be in a room with some ambient light (reflection from ceiling).

Is it worth trying bias lighting in my situation? My blacks aren't terrific to begin with...useable, but not great. I am sure the white ceiling doesn't help. Thanks!
You don't say if the screen is retractable or not. If not, perhaps a shadow box around the screen could help compensate somewhat for the white ceiling. Introducing bias lighting into a room with reflective room surfaces will only serve to diminish contrast and color saturation in a projected image. Contrast and black level are at the top of the widely accepted hierarchy of image quality characteristics.

Not having a dedicated room for a projection system can mean a wide variety of potential negative interfering compromises. Few of us can have an ideal setup. Therefore, the challenge and art of designing such systems involve how to set priorities for the compromises to performance that are inevitable. It's tough to advise how to balance compromises without seeing the room and discussing with the owners how the room is to be used when not watching the screen. Short of that, speculating on what potentially might be done usually wastes time.

We can't cheat the laws of physics. However, the study of imaging science exists for humans. Home theater is for enjoyment and relaxation, usually within the constraints of a limited budget.

Some will suggest that you get a light-rejection type of screen. I have yet to see one demonstrated that doesn't have hot spots, viewing angle restrictions, color non-linearities, and those obnoxious sparkles (most of us don't live in a glittery world).
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You don't say if the screen is retractable or not. If not, perhaps a shadow box around the screen could help compensate somewhat for the white ceiling.
It is not retractable. I've looked at a few options for the ceiling, but the wife isn't a fan. The walls are dark grey and matte. The floor is light colored too, but I built an entertainment stand that has Mouse Ear paint and a matte lacquer. It holds equipment, but helps with floor reflections. The furniture is also all dark, so that helps too.

Thanks for the insight as bias lighting is a no-go for me.
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post #10 of 19 Old 04-28-2017, 06:33 PM
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Anti-Reflective Prescription Glasses with Dolby 3D Glasses

Scott, in this podcast, you mentioned that you have issues with the Dolby 3D technology because you get extraneous reflections when wearing Dolby 3D glasses together with your prescription glasses. Looking at your glasses in the video podcast, I noticed the white glare of lights coming off of your glasses, which indicates that your glasses don't have anti-reflective coatings. If those are the same glasses you wear with the Dolby 3D glasses, that may contribute to your seeing reflections while watching Dolby 3D movies.
I have anti-reflective coatings on my prescription glasses, both inside and out, which seems to reduce reflections to around 25% of what they would have been--probably like the coating on TV sets. They have a muted green reflection as opposed to a full white reflection from light sources visible to me with your glasses.
If you haven't tried glasses with anti-reflective coating--both for long distance and computer glasses, I highly recommend them.
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bias light for projectors - crazy

I watch movies on a 100+" wide front screen projector in complete darkness, and would have a bat cave if possible. I watch my screen anywhere from 14-30 ftL, depending on if I want high contrast or high brightness. I don't notice eye fatigue on 2 Hr movies at 30 ftL.

While adding a bias light in a darkened room may reduce eye strain, it would negatively impact the viewing experience. It would be distracting (even when sitting in the center of the row, I find the floor lighting to the sides in a movie theater very distracting). It would reduce perceived contrast (people add black screen masking to increase perceived contrast). And it would destroy your ability to discern shadow detail.

So even if I had a hard time getting through a 2 hr movie due to eye strain, I would still prefer that to those negative effects.
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post #12 of 19 Old 05-02-2017, 11:06 AM
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I watch movies on a 100+" wide front screen projector in complete darkness, and would have a bat cave if possible. I watch my screen anywhere from 14-30 ftL, depending on if I want high contrast or high brightness. I don't notice eye fatigue on 2 Hr movies at 30 ftL.

While adding a bias light in a darkened room may reduce eye strain, it would negatively impact the viewing experience. It would be distracting (even when sitting in the center of the row, I find the floor lighting to the sides in a movie theater very distracting). It would reduce perceived contrast (people add black screen masking to increase perceived contrast). And it would destroy your ability to discern shadow detail.

So even if I had a hard time getting through a 2 hr movie due to eye strain, I would still prefer that to those negative effects.
Some individuals are less sensitive to eye strain than most.

"Contrast could be considered to be the most significant quality that impacts not only the perceived depth of an image, but also affects the apparent sharpness.....While the luminance level of a given image affects how the eye perceives contrast and detail, the ambient conditions surrounding the image can also have a dramatic impact. This phenomena was studied by Bartleson and Breneman (1967) to examine the impact of perceived contrast based not only on the luminance level of the image but taking into account the surrounding ambient luminance levels as well. Their results showed that the perceived contrast increased as ambient luminance increased. With the increase in ambient luminance, the eye interprets black levels as being darker while the impact to the white level is minimal. Since the perceived difference in dark areas is greater under the higher ambient luminance conditions, the perceived contrast is higher. It is a natural tendency to want low ambient luminance levels to strive for "better" perceived image quality and what is thought to result in higher contrast. However, in reality, the opposite is true. This tendency may be justified for current direct view CRT televisions due to the issue of glare that results from the glossy surface of the glass tube [also true for certain flat panel displays today]. With less ambient luminance, the glare is reduced- but it may be important to keep some ambient luminance behind the television [as in the case of bias lighting] to keep the perceived contrast higher.....While sharpness can affect the apparent contrast of an image, the converse is true in that contrast can also impact the apparent sharpness of an image. Images that have lower contrast will appear to be not as sharp as an image of the same content, but with higher contrast.....A subjective study was then conducted to verify the impact that ambient lighting has on perceived contrast. Several non-technical (and thus presumably non-biased) and technical observers were asked to compare a series of images with various ALL [average luminance levels] under different ambient luminance extremes in order to understand the impact that ambient viewing conditions might have on the perceived contrast between the two television technologies [CRT and DMD (DLP RPTV)]. Under dark ambient conditions, the result for images with an ALL > 5% was found to be equal between the CRT and the first DMD display. However, under bright ambient conditions (about 250 nits of luminance on the wall behind all of the units), the DMD display was favored over the CRT by 50% of the observers as having higher perceived contrast.....This proved that ambient conditions have the effect of potentially raising the black level threshold of the eye above the actual black level of the television such that the perceived contrast ratio is higher." from the SMPTE Journal, 11/02. 'The Importance of Contrast and its Effect on Image Quality' by Segler, Pettitt and Kessel

"Their experimental results, obtained through matching and scaling experiments, showed that the perceived contrast of images increased when the image surround was changed from dark to dim to light. This effect occurs because the dark surround of an image causes dark areas to appear lighter while having little effect on light areas (white areas still appear white despite changes in surround). Thus since there is more of a perceived change in the dark areas of an image than in the light areas, there is a resultant change in perceived contrast.....Often, when working at a computer workstation, users turn off the room lights in order to make the CRT display appear of higher contrast. This produces a darker surround that should perceptually lower the contrast of the display. The predictions of Bartleson and Breneman are counter to everyday experience in this situation. The reason for this is that the room lights are usually introducing a significant amount of reflection off the face of the monitor and thus reducing the physical contrast of the displayed images. If the surround of the display can be illuminated without introducing reflection off the face of the display (e.g., by placing a light source behind the monitor that illuminates the surrounding area), the perceived contrast of the display will actually be higher than when it is viewed in a completely darkened room." from 'Color Appearance Models,' by Mark D. Fairchild, Ph.D., of the Chester F. Carlson Center for Imaging Science: Munsell Color Science Laboratory

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post #13 of 19 Old 05-02-2017, 02:33 PM
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Some individuals are less sensitive to eye strain than most.

"Contrast could be considered to be the most significant quality that impacts not only the perceived depth of an image, but also affects the apparent sharpness.....While the luminance level of a given image affects how the eye perceives contrast and detail, the ambient conditions surrounding the image can also have a dramatic impact. This phenomena was studied by Bartleson and Breneman (1967) to examine the impact of perceived contrast based not only on the luminance level of the image but taking into account the surrounding ambient luminance levels as well. Their results showed that the perceived contrast increased as ambient luminance increased.
...
I agree that placing a lighter surround near a darker edge of the screen will make that part look darker. But I don't really care about making a dark screen edge seem darker, because it has some light gray border next to it. The contrast that counts is within the image, and placing a gray surround next to the screen edge will also make it more difficult to see subtle detail within the black area. Seeing more detail in a scene is not just about black next to white, but details throughout the range of brightness.

The picture border should not draw your attention, and to me it is similar to someone off to the side playing with their smart phone. The light inteferes with your vision, and is bothersome.
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post #14 of 19 Old 05-02-2017, 04:08 PM
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I agree that placing a lighter surround near a darker edge of the screen will make that part look darker. But I don't really care about making a dark screen edge seem darker, because it has some light gray border next to it. The contrast that counts is within the image, and placing a gray surround next to the screen edge will also make it more difficult to see subtle detail within the black area. Seeing more detail in a scene is not just about black next to white, but details throughout the range of brightness.

The picture border should not draw your attention, and to me it is similar to someone off to the side playing with their smart phone. The light inteferes with your vision, and is bothersome.
It does not just affect the outer edges of the image on the screen. Bias lighting affects perception of the darker portions of the entire image (as described in the articles quoted above) when viewing both in a dark room. It triggers a perceptual response in the visual cortex of the brain. Bias lighting should be implemented in such a way that the light is not directly visible to the viewer and is constant, unlike a cell phone being used by another audience member. It should be installed so that it washes the wall behind and around the screen. The wall should also be a neutral gray color.
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It does not just affect the outer edges of the image on the screen. Bias lighting affects perception of the darker portions of the entire image (as described in the articles quoted above) when viewing both in a dark room. It triggers a perceptual response in the visual cortex of the brain. Bias lighting should be implemented in such a way that the light is not directly visible to the viewer and is constant, unlike a cell phone being used by another audience member. It should be installed so that it washes the wall behind and around the screen. The wall should also be a neutral gray color.
If what you say is true, why do people add expensive (very black) masking to their home theater setups?

In the mid 90s, I had a 46" RPTV. When watching scope movies, I would add top and bottom velvet lined panels to cover up the "black bars" (really gray bars). The improvement to the perceived image was unmistakeable. It was totally obvious and not subtle.

If the effect you describe were "true", wouldn't we see Dolby, IMAX, or at least someone doing it?

There already is a form of surround light in many of the super big screen theaters from emergency exit lights, and floor lighting illuminating the unmasked part of the screen (e.g. IMAX uses 2:1 screen with no masking when showing 2.4:1 movies, leaving top/bottom bars ). Even though this is at very low light levels, I find it distracting and annoying.
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[...] from the SMPTE Journal, 11/02. 'The Importance of Contrast and its Effect on Image Quality' by Segler, Pettitt and Kessel

[...] by Mark D. Fairchild, Ph.D., of the Chester F. Carlson Center for Imaging Science: Munsell Color Science Laboratory
These are very interesting findings. So would a gray screen in front of a white/light gray front wall with all other room boundaries painted (near) black increase perceived picture contrast? The white/light gray front wall would act as a bias light (there's always some stray light) and the black room would largely prevent light from being reflected back onto the screen, i.e. contrast is maintained.

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post #17 of 19 Old 05-03-2017, 12:37 PM
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These are very interesting findings. So would a gray screen in front of a white/light gray front wall with all other room boundaries painted (near) black increase perceived picture contrast? The white/light gray front wall would act as a bias light (there's always some stray light) and the black room would largely prevent light from being reflected back onto the screen, i.e. contrast is maintained.
Some of the theory might apply, but the wall would change in brightness along with picture content reflecting in the room. Try it and let us know what your results were.

There are a couple of "sticky" threads that cover some of these issues in the display calibration section of the forum:

'How Viewing Environment Conditions Can Corrupt Or Enhance Your Calibration.'

https://www.avsforum.com/avs-vb/showthread.php?t=849430

'D65 Video Bias Lighting- Fundamental Theory And Practice'
https://www.avsforum.com/avs-vb/showthread.php?t=1162578

The bias light thread includes these illustrative graphic demonstrations:

Graphic depictions of ambient lightness enhancing perceived black and contrast:
;
;
;
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post #18 of 19 Old 05-03-2017, 12:44 PM
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Also, here is a link to an additional variety of graphical demonstrations under the 'Brightness illusions' heading:

http://www.labofmisfits.com/articles...onsoflight.asp
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post #19 of 19 Old 05-03-2017, 12:51 PM
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If what you say is true, why do people add expensive (very black) masking to their home theater setups?

In the mid 90s, I had a 46" RPTV. When watching scope movies, I would add top and bottom velvet lined panels to cover up the "black bars" (really gray bars). The improvement to the perceived image was unmistakeable. It was totally obvious and not subtle.

If the effect you describe were "true", wouldn't we see Dolby, IMAX, or at least someone doing it?

There already is a form of surround light in many of the super big screen theaters from emergency exit lights, and floor lighting illuminating the unmasked part of the screen (e.g. IMAX uses 2:1 screen with no masking when showing 2.4:1 movies, leaving top/bottom bars ). Even though this is at very low light levels, I find it distracting and annoying.
Joe Kane's suggestion for implementing bias lighting in HDR cinema presentations was regarding potential eye strain relief. Such cinemas are relatively new. Standards and recommended practices for HDR in cinema and homes are yet to be completely defined. Stay tuned.
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