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.

1 Comment
  • John Bishhop

    Great overview of current TV tech JS. TV’s became a part of the HT Lexicon when surround sound was still analog and TVs were CRT. I see RAYVA as genuine cinema, not HT. It is a dedicated space designed to professional cinema’s standards with cinema technology to display the art of movies. All of that to convey the experience directors intended for us when they made their movies. TVs never have and don’t today provide a genuine cinema experience. Even Sony OLED pro monitors are not the reference for the cinema image or experience. They are a tool, like the daily rushes were in the days of film. Directors and DP’s use monitors to see their work in process. They translate the monitor’s image to imagine what it will be like in genuine theatrical release, and we get that in a RAYVA theater if we do our jobs right. But not to be flip, I have a 75″ in the Living Room that does HDR10 and Dolby Vision, which is why I bought it. I have a native scope 2.35:1 flat panel TV in my theater for monitoring content, but my cinema screen is a 5′ high 2.55:1 aspect ratio reference white surface with a reference 3-chip DLP. And it is 1080p. Resolution is not pixel count in cinema, which is why 80% of digital cinemas are 2K. It’s adjacent pixel contrast that defines sharpness, and at 1.5 screen heights from the screen, pixel structure is invisible. TV makers pushed 3D, now they don’t. They pushed 4K 2160, but it wasn’t a visible benefit and we all knew it, and today even most analysts agree. Next came high frame rate (odd push for LCD tech) and now it’s HDR, WCG, & HFR. These are not cinema debates as much as how TV brands make yesterday’s models suck in order to sell us the next one. Cinema is closer to professional cameras. The film derived images of Ansel Adams and the digital images from Leica cameras from a decade ago are the same quality of art today as they were then. Theaters built on the 2K platform display movies perfectly well, to a rational standard developed by professionals. Parameters like contrast at the pixel level and up, color gamut and accuracy, flat field uniformity, and white field purity are all areas that challenge TV’s. HDR is still an experiment in cinema, where a tiny few theaters can even show it. We’ll see. But for now, there are 25,000 movies waiting to be screened in cinematic glory in our private theaters, and they are all 1080p Rec 709 blu rays. Meanwhile, there are just 25 UHD HDR movies to watch, and only one at HFR. You can exhaust the entire UHD library in a couple weekends. Let’s not get the cart too far in front of the horse. Good design will consider all relevant content and make best decisions to optimize the image for the budget allotted. The TV world is caught up in their own feature fight death match. Cinema is not so much. That’s to our benefit where building rooms of lasting value is a worthy goal.

    August 3, 2017 at 5:08 pm