Ultra HD Tag

Video Displays: How Good Is Good Enough? Pt. 2

video display innovations

The Avatar sequel is reportedly being shot at 120 frames per second—5 times the
frame rate of the traditional 24 fps.

In Pt. 1, I discussed how improvements in color space and dynamic range are bringing video displays closer to the abilities of the human eye. Here I’m going to discuss the impact of spatial resolution and refresh or frame rate.

 

Pixels get all the attention when most people pick out their TVs. 2K, 4K, 8Khow many K’s do I need? But just because a display can put more pixels on the screen doesn’t mean they’re better pixels. 

 

Everyone has had the experience of going to the eye doctor and straining to see if that E is pointing up or down, or left or right. As you go from the top line to the bottom, there’s a point where you can no longer determine which direction the E is pointing. This is how the eye doctor determines your sensitivity to spatial resolution.

 

My eyes aren’t quite as good as they used to be, but on a flat-screen TV, I can see pixels on a 1080 display when I’m standing about 3X the picture height back. On a 4K, I can’t see pixels until I get inside of 1.5X the screen height. With projectors, you need to be even closer to see pixels as a result of the natural smoothing affect of convergence and optical lenses.

 

If I’m staring at a spreadsheet, those pixels and distances are pretty accurate, much like staring at those E’s at the eye doctor. But if I’m watching a movie, I’m not straining my eyes to see pixels but instead want to take in the whole image, so I’m moving further back. 4K allows me to sit comfortably about 2X the screen height back, which is as close as I’d ever want to watch a movie. So for the future, don’t give me more pixels, give me better pixels!!!

 

So far, I’ve been talking about pixels, but unless I’m only talking about spreadsheets, I need to understand more about how the human eye sees motion. After all, I want to watch movies!

video display innovations

James Cameron, of Avatar fame, was one of the first Hollywood producers to push HFR (high frame rate). The original movie spec was 24P, and it was chosen because it was the lowest refresh to allow acceptable audio quality. This means that the entire image on the screen is refreshed 24 times per second.

 

If I’m watching two people sitting across a table from each other talking, slow frame rate doesn’t bother me. But if I’m watching a plane fly across the sky, or Matt Damon jumping from one building to another in a chase scene, I need faster refresh rates. When you look in the sky and see a plane fly by, you see it move in a nice, smooth continuous motion. But when you watch a movie in 24P, the plane will seem to jump across the screen as it moves from frame to frame. Your brain naturally tries to smooth this out, but when you watch two scenesone with HFR and one withoutyou appreciate the difference.

 

The critics say HFR makes images seem “soap opera”-like, but honestly, isn’t that the way we see things in real life? When we walk through everyday life, does the world look more like a soap opera or a movie? (I did say “look” and not “feel.”)

 

So currently we hover between 24P for movies, and 60P for video. Experts seem to feel that the threshold for the human eye is around 120Hz (which is what the Avatar sequel is rumored to be shot in). Let me please note that HFR means the movie or content was shot or captured in this high frame rate, not just displayed at faster refresh.

 

Many flat panels tout 240Hz or even 600Hz refresh, but that is just refreshing the same content on the panel and is intended to fix deficiencies in the panels, not in the quality of the movie. HFR requires a lot of bandwidth, so improvements here are costly, but they have a big impact on the way we see images. So expect this to take a little longer than the other items discussed here.

 

In the past 10 years, we’ve seen improvements in all aspects of display performance that affect visual acuity. In the next 10 years, we will see even more improvements. The most important thing is that it’s not just about resolution. Getting to 8K will not bring us to the ultimate display.  In fact, most people won’t see any improvement from going from 8 million pixels to 33 million pixels. If we all want to watch video and have it replicate real life, we don’t really need more pixelswe need better pixels. Give me pixels with more color, more contrast, and refresh them on the screen faster. In the meantime, give me content that will really take advantage of all that my current 4K UHD display can handle. 

—George Walter

A 25-year veteran of the video-display industry, George Walter has been a vice president
at Digital Projection, where he founded its residential division, and a board member for both
CEDIA and Azione. George is the President of Rayva.

REVIEWS

Wonder Woman review
Blade Runner: The Final Cut review
Lawrence of Arabia review

Video Displays: How Good is Good Enough?

TV innovations

The last few years, we’ve seen continual improvement in the performance of flat-panel TVs and projectors. Where will it stop? What is the Holy Grail in video display anyway?

 

The answer to that question is different for everyone, but the solution is the same. When the display is capable of creating an image that meets all the limitations of the human eye, there’s no reason to keep improving. Everyone’s eyes see the world slightly different, whether it be color, contrast, sharpness, or action. That’s why some people hate 3D and others love it. (But that’s a topic for another discussion.)

 

To compare what a typical person can see versus today’s top displays, we need to look at four areas that affect the imaging in the human brain: color, contrast, spatial resolution, and refresh or frame rate.

 

First, let’s look at color. We’ve recently heard talk about “color space” or “color gamut.” This is defined in fancy three-dimensional charts, but basically it’s the total volume of color the eye can see or a display can create. 

 

When REC 709—the color standard for HDTV—first came out, it could reproduce about 35% of the total colors the human eye can see. P3, or digital-cinema color space, took the amount to about 50%. Most of us—especially those of us who remember NTSC—think this looks incredible, and yet we’re still only at 50%.

TV innovations

The triangle within the chromaticity diagram on the left shows the color space for HDTV while
the triangle on the right shows the significantly expanded color space for 4K Ultra High Definition

New discussions are about REC 2020, which will take the total color space to 75% of what the eye can see. Some flat panels can do this now, but projectors have a tough time reaching this with conventional lamps and will require pure RGB laser to achieve both the color space and light output needed to really appreciate all those colors.

 

In roughly 10 years, we’ve doubled the color space that can be seen on a consumer display, yet very little content is available to appreciate the full scope of this improvement. There’s still some room for improvement, but the big gains have already been accomplished.

 

Now let’s look at contrast. The human eye is an amazing organ. If you remember from science class, it’s made up of cones and rods, which are microscopic sensors that can detect content and send images to the brain.

 

Rods work at very low light levels (like when you wake up in the middle of the night) and cones need a lot more light and are used to see color. At night, the iris in our eye opens up to let more light in, but the rods don’t detect much color so we pretty much see in black and white. In this condition, we can see a lot of detail in black levels. On a nice sunny day, we get lots of light and color into our eye, and the cones take over. If we compare what the human eye can see in low light levels to what we can see in bright daylight, our range of contrast is huge.

TV innovations

HDR (high dynamic range) comes much closer to approximating human vision than
does SDR (standard dynamic range)

This is the magic of HDR. By applying different values to bright scenes than it does to dark ones, it more closely matches how the human eye responds, providing much more dynamic contrast. HDR has the most overall impact on picture performance than anything we’ve seen since HDTV, and yet few can explain how and why it works. (Not to mention that there are so many watered-down variations.) But let your eye decide, and it will see the impact of HDR every time from anywhere in the room. 

 

In Part 2, I’ll talk about spatial resolution, refresh or frame rate, and why pixel counts aren’t as important as you might think they are.

George Walter

A 25-year veteran of the video-display industry, George Walter has been a vice president
at Digital Projection, where he founded its residential division, and a board member for both
CEDIA and Azione. George is the President of Rayva.

REVIEWS

Wonder Woman review
Blade Runner: The Final Cut review
Lawrence of Arabia review

Why UHD Is Way Better Than HDTV–Pt. 2

Ultra HD

In yesterday’s post, I talked about how resolution and HDR (High Dynamic Range) contribute to making Ultra HD TVs and projectors a huge leap over traditional HDTVs. Here are the other two things you need to know about UHD.

 

Color

A new term you might hear when considering Ultra HD is “wide color gamut,” which refers to the significantly larger amount of colors a UHD set can produce compared to an older TV. Imagine the colors a TV can produce as a triangle, with the primary colors red, green, and blue making up the three points. Those three color points determine the number and accuracy of all the colors a TV can reproduce. New TVs produce an expanded triangle of colors, pushing the boundaries of the triangle further out at all three corners to encompass more of the colors the human eye can see. That means you’ll notice brighter, more vibrant colors than ever beforedeep crimson reds, vibrant greens, and cool, tropical blues that will pull you into the image.

Ultra HD
Bit Depth

The most technical area of the bunch, bit depth refers to the number of shades of color a TV can produce. TVs in the past used 8-bit color depth, which meant they could produce roughly 256 shades for each of the three primary colors256 shades each of blue, red, and green. Multiply those together and you arrive at the nearly 16.8 million colors a last-generation TV could produce.

 

Modern Ultra HD sets up the ante to 10 bits, and while a couple of bits might not seem like a lot, since bit rate is logarithmic, it’s actually a massive improvement. How massive? Modern sets can produce 1,024 shades per color, making for the ultimate Crayon box of more than 1 billion colors! That means not only a tremendously more lifelike image, but it also eliminates any color banding as colors transition from one shade to another.

Ultra HD TV

Individually, any one of these four improvements would be a big step beyond HDTV, but when employed together, these upgrades mean Ultra-high-defintion TVs produce the best, most lifelike images imaginable, making UHD TV a must buy for any true videophile!

—John Sciacca

Probably the most experienced writer on custom installation in the industry, John Sciacca is
co-owner of Custom Theater & Audio in Murrells Inlet, South Carolina, & is known for his writing
for such publications as
 Residential Systems and Sound & Vision. Follow him on Twitter at

@SciaccaTweets and at johnsciacca.com.

ALSO ON CINELUXE

Why UHD Is Way Better Than HDTV–Pt. 1

HDTV vs Ultra HD TV

If you’re in the market for a new TV or projector, you’ve likely been bombarded by a lot of new terms and technologies you haven’t heard before. Ultra HD (aka Ultra-high-definition or UHD) burst onto the scene a few years ago and brought with it some major changes and improvements to our display systems. And now that prices are reaching mass-market levels, it would be foolish to buy a new set that wasn’t Ultra HD.

 

Wondering what all the fuss is about? In today’s post, I’ll talk about the first two things you need to know about this exciting new video tech and will discuss the final two tomorrow.

 

Resolution

The height of home video prior to Ultra HD was called 1080p, with the “p” standing for “progressive.” Those sets produced 1,920 horizontal pixels and 1,080 vertical pixels for a total of just over 2 million pixels on screen at any moment. UHD doubles the number of pixels in both directions, producing a resolution of 3,840 by 2,160, delivering nearly 8.3 million pixels on screen, or four times the amount of 1080p. That is why Ultra HD is often referred to as “4K”.

 

What do all those extra pixels mean? Greater definition, razor-edge sharpness, and finer details. Video artifacts like “jaggies” and “moire” are a thing of the past. Every strand of hair, every blade of grass, every grain of sand shows up like never before. As an illustration, imagine if you had a pencil and drew two same-sized circles, one with 10 dots and one with 40 dots. The 40-dot circle would have more resolution and be better defined. That’s the difference between 1080p and UHD.

HDTV vs Ultra HD TV
HDR

HDR is another term you’re going to hear a lot. It stands for High Dynamic Range, and it’s actually more important for picture quality than all those extra pixels. If you’ve taken any pictures on a modern smartphone, you’ve probably noticed the HDR tag. It works by capturing images with different exposures and then combining those separate images into a single photo that maintains the detail from the darkest and brightest regions.

 

In the past, TVs would “crush” the image at one end of the spectrum or the other, sacrificing black levels in bright scenes or lowering overall light output in dark scenes. But new Ultra HD TVs can simultaneously produce deep, dark blacks and bright, brilliant whites, meaning they can deliver images more like what your eye is capable of seeing. This gives the image great contrast, and delivers punch, depth, and reality like never before.

 

In Pt. 2, I’ll walk you through the other two crucial things you need to know about Ultra HD.

—John Sciacca

Probably the most experienced writer on custom installation in the industry, John Sciacca is
co-owner of Custom Theater & Audio in Murrells Inlet, South Carolina, & is known for his writing
for such publications as
 Residential Systems and Sound & Vision. Follow him on Twitter at

@SciaccaTweets and at johnsciacca.com.

Billy Lynn’s Long Halftime Walk

Kaleidescape Billy Lynn's Long Halftime Walk

Since the dawn of cinema, the established film frame rate has been 24 frames per second (fps). However, Thomas Edison said the visual cortex needed at least 46 fps to avoid eye strain. To achieve this, and eliminate any eye strain or strobing, many modern 35 mm film projectors use two- and even three-bladed shutters—flashing each frame on the screen two or three times—to achieve 48 and 72 images per second to satisfy Mr. Edison’s recommendation.

 

Yet, despite all the technological advances over the past century, all those movies you’re watching in your fancy home theater—whether via DVD, Blu-ray, and even Ultra HD Blu-ray player—are being shown at that same 24 fps.

 

Except one.

 

My latest pick for Movie of the Week is Billy Lynn’s Long Halftime Walk, not because it’s a great film—in fact, it’s kind of a mess of a story—but because it looks so frickin’ amazing that it’s the brain and eye candy your visual cortex has been craving!

 

Billy Lynn is so impressive because director Ang Lee used an extraordinary shooting style, filming at 4K resolution in stereoscopic 3-D at 120 fps—five times the traditional rate. This is the highest frame rate ever used on a film, eclipsing the 48 fps Peter Jackson employed for The Hobbit: An Unexpected Journey. This approach resulted in more than 540 terabytes of dailies with a final delivery file that was 84 TB.

 

But since only six theaters in the world—including just two in the US—could actually show the film in its full glory, you probably never saw it. And since 4K/120 exceeds the Ultra HD and HDMI 2.0 spec, Billy Lynn has been released to the home market in 4K at 60 fps, the highest resolution the format can support. This high frame rate requires the full 18 Gbps bandwidth, and will lay bare any shortcomings in your system’s signal chain. But for those lucky enough to experience it in its full 4K/60 glory, Billy Lynn looks absolutely stunning and unlike any movie you’ve seen before.

 

There’s hyper clarity and focus in every shot. Tight shots on actors’ faces reveal every thought, detail, and expression down to the thinnest individual strand of hair. Fabric in actors’ uniforms reveals texture and micro stitching detail, letting you see every nuance of the patches and medals, and even analyze the diamond pattern on rifle grips. Wide shots capture every actor, building, and set piece in razor-sharp focus. One of my favorite shots happens at 6 minutes 34 seconds, where you can read details on the gravestones many rows back in the cemetery, and when the camera pans over to the service, the image remains solid and focused. 

 

From an audio standpoint, Billy Lynn includes an immersive Dolby Atmos mix that helps establish the ambience in different scenes. While the first half of the film is a bit restrained, the second half starting with the actual halftime show kicks into high gear, with the big battle scene in Chapter 11 being reference quality all the way.

 

Kaleidescape Strato owners need to be sure to download the HDR version of Billy Lynn’s Long Halftime Walk, since that’s the 60 fps version. While you might not love the movie, it’s sure to become your go-to video demo material when you want to impress your guests and demonstrate what the fuss about 4K HDR is all about!

—John Sciacca

 

—> Check out John’s post on “How Kaleidescape Delivers Real HD”

Probably the most experienced writer on custom installation in the industry, John Sciacca is
co-owner of Custom Theater & Audio in Murrells Inlet, South Carolina, & is known for his writing
for such publications as
 Residential Systems and Sound & Vision. Follow him on Twitter at

@SciaccaTweets and at johnsciacca.com.