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technology

8K Displays: Awesome Potential, But…

Advances in display tech mean better picture quality, but there are still some tradeoffs. By Joel Silver and David Danto This year’s CES show—the 52nd in its history—continued the transition of this exposition from a “products” show to a “concepts” show. As the topics get more amorphous, it becomes obvious how hard it is to demonstrate new solutions using a conventional physical booth—one can’t very well showcase artificial intelligence (AI) or 5G with a model holding them in his or her hands. But then, bucking the trend, there are always the latest displays to touch, feel and, of course, see. At CES 2019, industr y people and the media gathered around, ogled and drooled over a number of displays that all boasted the newest and hottest feature: 8K resolution. Yes, some of the images were fantastic and certainly created a “buying lust”—even among the financially challenged press corps. However, there were some striking differences in the quality of the images on the various displays showcased. Mixed in with the standouts were 8K models whose picture quality was soft and fuzzy, artifact-ridden and downright fatiguing to watch. Once again, hyping the hottest buzzword didn’t necessarily equate with having the best product.

Perceived Picture Quality

8K, in and of itself, is no nir vana. Perceived picture quality is always going to be dependent on the quality of the content, the quality of any devices processing the image, the quality of the medium that brings the image to the display and the manufacturing quality of the display itself. Yes, 8K displays can be awesome, but, with distribution challenges and hardly any native content, taking the leap to 8K today in the commercial integration world would likely be foolish. In order to understand where and

how 8K fits as the latest entrant into the display world, it’s helpful to look at the “Space, Light and Time” classification of digital displays. After all, digital TVs (DTVs) are simply machines that turn bits into pictures—they transform digital data into physical images using space, light and time. Space: The number of visible lines or pixels onscreen. Light: How bright the picture is, and how many colors are visible onscreen. Time: How many pictures are flashed per second; in other words, “temporal resolution” or frames per second (fps). The first digital displays—released in 1982—digitized our old analog TV images (the ones that used either 525 or 625 TV lines.) So as better to understand how these displays evolved into 8K TV, let’s start at the beginning with how analog displays brought pictures into our homes and trace the evolution of these space, light and time parameters to our current era of ultra-HD displays, including 8K. ANALOG TV Space: Either 525 or 625 horizontal lines top to bottom Light: Tube TVs (CRTs) had a brightness of only 100 nits, but had unlimited steps between black and white Time: Either 50fps or 60fps, unchanged since the 1930s STANDARD-DEFINITION DIGITAL REC. 601 Space: 640x480, or roughly 300,000 (.3K) pixels to process Light: 100 nits, 220 steps from black to white at 8-bit, CRT TVs’ phosphor-based colors Time: The same 50/60fps since the 1930s HIGH-DEFINITION DIGITAL REC. 709 Space: Up to 1920x1080, or roughly 2,000,000 pixels (2K) Light: 100 nits, 220 steps from black to white at 8-bit, but somewhat improved to 1990 CRT colors Time: The same 50/60fps since the 1930s ULTRA-HIGH DEFINITION—2012 SPECS BT.2246-1 Space: Up to 8K—roughly 33,000,000 pixels Light: Up to 10,000 nits, roughly 1,000 steps from black to white at 10-bit, roughly 4,000 steps at 12-bit Time: Up to 120fps. “Temporal resolution” is finally improved—and sports look awesome!

Beauty & The Beast

The first thing to realize about any DTV is that creating perfect analog pictures using bits will never happen. DTV deploys elementar y calculus using “points” to emulate a “cur ve,” and the cur ve can never be completely smooth. But with more points from higher bit depths, and more places to spatially posi-

Joel Silver is the President and Founder of the Imaging Science Foundation, Inc. (ISF), which incorporated in 1994 to introduce image-quality-improving calibration services into HDTVs. There are now more than 12 million HDTVs shipped each year under license to the ISF.

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IT/AV Report

Profile for Sound & Communications

IT/AV Report Spring 2019  

Topics featured in this issue include Understanding AV Over IP, 2019: The Do or Die Year for Enterprise Team Chat Solutions, The Changing Fa...

IT/AV Report Spring 2019  

Topics featured in this issue include Understanding AV Over IP, 2019: The Do or Die Year for Enterprise Team Chat Solutions, The Changing Fa...