Showing posts with label 4K. Show all posts
Showing posts with label 4K. Show all posts

Feb 10, 2017

4k UHD, HDR-10 (Dolby Vision), OLED, Smart TV

Since the last time I wrote about TVs some new acronyms have popped up. If you are buying a TV for the future these are important, but if you are buying a TV for short term, (the next few years) almost all of these are not important. The reason they are not important is because almost no one is broadcasting to take advantage of 4K, HDR-10, (Dolby), except some Netflix and Bluray DVDs.

Smart TV - These sets are good to have now and the majority of new TVs are smart TVs. They allow access to the internet from your home WiFi and provide access to Netflix, YouTube, Hulu, and more without the need for a separate box.
Many Smart TVs give you a full web browser, so you can use a search engine or visit websites. Some let you play interactive online games.

4K UHD - these ultra-high-definition televisions offer four times the resolution of a standard 1080p HDTV. Instead of a screen that has about 2 million pixels, these televisions show about 8 million pixels.

HDR-10, Dolby Vision - I lump these two, High Dynamic Range and Dolby10 together, because they are competing technologies, kind of like the old Betamax / VHS argument. Some manufactures are using one vs. the other and some have both. HDR is currently winning, because it is open source while manufacturers must pay royalties to Dolby for its technology. Many advertisements refer to them simply as Dolby and HDR.

The first of the two major differences between Dolby Vision and HDR-10 is that Dolby uses 12 bits per color (red, green, and blue), where HDR-10 uses 10 bits per color. The second, Dolby Vision uses dynamic, or continuous metadata so that color and brightness levels can be adjusted per scene, or even frame-by-frame basis. HDR-10 uses static metadata that is sent only once at the beginning of the video. Both reproduce a wider range of brightness levels, higher contrast ratio, and richer colors. Contrast ratio is the measurement of the difference in brightness between the whitest white and the darkest black. When seen side by side with non-HDR content, HDR-enhanced video is incredibly bright and with vibrant colors. Samples show a very positive marked difference.

Some TVs use OLED (Organic Light Emitting Diode) screens for a superior image and other benefits. Televisions packed with organic light-emitting diodes are incredibly thin, because each pixel is its own light source, so backlighting is not required. These televisions are more energy efficient than other TV panel types. Some LG TVs are as thin as four credit cards.
Quantum dot  or QLED TVs can match the contrast ratio of OLED. Quantum dots are microscopic dots about a fraction of the width of a human hair.Samsung uses the term Quantum Dot.


Bottom line, you can get 4K UHD, HDR (Dolby), OLED on one TV. Every 4K is UHD by definition. Almost all TVs are LED, but very few are OLED or Quantum dot. Most TVs are now Smart TVs.

Incidentally, DolbyVision is for pictures and Dolby Atmos is for sound.

Jan 22, 2016

Screen Resolution Evolution

Now that the 2016 Consumer Electronic Show has ended, it seems appropriate to recap where we are with TVs and how we got here.

First, 3D TV is dead. Curved screens remain a hard sell. 4K TV is looking at a short life span as it is already being usurped by 8K TV. 8K may suffer the same fate unless TV and movie producers begin to crank out content capable of utilizing the new standards. In times past, we always waited for hardware to catch up to our needs, now we are waiting for content to catch up to hardware.

Sharp released its first 8K TV in 2015. The 85-inch LV-85001 costs $133,000. Samsung showed its 110-inch 8K TV in January, 2016. It also announced that a 11K TV is being developed for the 2018 Pyeongchang Winter Olympics. LG also showed off a 98-inch 8K TV in January, 2016. All of this advancement comes amid a current dearth of 4K content. These advances may still prove to be more resilient than the 3D revolution that never happened.

Advances in hardware and software continue to outrun battery capacity and bandwidth speed. Although bandwidth is less of an issue in Europe and other countries as the US continues to lag, mostly due to politics, not capability.

How we began the race comes from early television. For the first half-century of television, resolution was measured in lines per screen rather than pixels. TV resolution in the 1930s and 1940s had 240 to 819 lines per screen, improving upon previous resolutions. The new resolution used a display method known as progressive scanning, where each line of an image is displayed in sequence, in contrast to the traditional analog method where first odd and then even lines are drawn alternately.

In 1953, analog color TV had 525 lines, establishing the NTSC color standard. Europe followed up in the 1960s by introducing the 625-line standards. However, bandwidth barriers limited widespread adoption of analog HDTV.

In 1977, the Apple II introduced color CRT display to home computers by adapting the NTSC color signal. The Apple II achieved a resolution of 280 pixels horizontally by 192 pixels vertically. By the 1980s, home computer makers began using pixels (picture elements) as a unit of measure.

IBM introduced a VGA standard display of 640x480 in 1987. Since then, demand for digital videos and video games has driven resolution to greater and greater density. Desktop monitors are now a standard resolution of 2560x1600. Mobile devices range lower from 240x320 for the smallest devices.

During the 1990s, plasma TVs and LCD TVs moved toward thinner and lighter TVs. During 1996, digital was officially mandated by the US FCC as a new standard for future DTV/HDTV broadcasting. By 2006, LCDs became more popular due to better daytime viewing and lower prices. LCDs created colored images by selectively blocking and filtering a white LED backlight rather than directly producing light.

HDTV uses a resolution of 1920x1080p, equivalent to 2,073,600 pixels per frame, and known as 1080p. The 4K Ultra HDTV uses 3840x2160p, known as 2160p. This amounts to four times the amount of pixels and twice the resolution of HDTV, hence 4K. The newer 8K increases this eight times to 7680x4320.

OLED improved color by directly producing colored light, allowing for greater contrast. OLED TVs are also extremely thin, measuring in fractions of an inch.

When the iPhone 4 was released, Steve Jobs claimed that the human eye cannot detect smartphone resolution beyond 300 pixels per inch (Apple's limit at the time). However, many others have proven the eye can actually detect at least 900 or greater PPI.

Incidentally, it is the relationship of HD, 4K, 8K, etc., to screen size that makes the difference. Phone screens are small, so HD, 4K, etc., are a waste, as our eyes cannot perceive the difference. Distance between our eyes and the screen is also a factor, that is why many TV manufacturers show the optimal distance for viewing.

As TV sets grow, it takes more pixels to see the same clarity of picture that are needed on a smaller screen. The arguments of not being able to tell the difference between HD, 4K, and 8K are relative to size and distance from the screen. However, 8K is likely beyond the average household to notice any perceptible difference vs. 4K.

Jan 16, 2015

4K, 8K, LED, OLED, HD, UHD

There are a number of confusing TV terms being thrown around these days to catch our attention and drive us to toss out our relatively new flat screen TVs. I decided to decode a few of the terms so we can make an informed decision - and then rush out to buy something to get the 'first on the block' medal.

4K has about eight million pixels which equates to about four times more than a current 1080p TV. Think of your TV like a grid, with rows and columns. A full HD 1080p image is 1080 rows high and 1920 columns wide. A 4K image almost doubles both those numbers, so you could fit every pixel from your 1080p set onto one quarter of a 4K screen. Recent 4K TVs are the same thickness as a smart phone, less than two tenths of an inch thick.

Since 4K contains four times the information of High Definition (HD or FHD), someone came up with the name Ultra High Definition (UHD). The bad news is the Internet providers have not opened up the pipes enough, so many 4K users see a lag time (that frustrating spinning circle) when watching 4K content. Netflix and Amazon currently charge more for delivering 4K content.

Currently, 1080 resolution comes from the image height, while 4K (3840 x 2160) is derived from image width. If it was described the same way as now, 4K would be 2160p. Seems that was not enough of a difference to command the increased price so they changed the definition to make it seem better to the uninitiated.

8K (7680  x 4320) basically doubles the pixel height and width of 4K to about 32 million pixels. The 8K standard is currently for exhibitions and movie theaters. Since 4K will not become the norm for a few more years, 8K is many years away from the home market.

LED comes from Light Emitting Diode. LED TVs are really LCD TVs, but the difference is how the screen is lit. Traditional LCD TVs use florescent backlights, LED TVs use smaller, more energy-efficient LEDs. LED screens produce great color, but the brightness of the lights can also wash out blacks on the screen.

OLED or Organic Light Emitting Diodes have been around for years, but producing big screens using this technology has proven to be prohibitively expensive until lately. The OLED elements generate their own light so the technology is stunning, with vibrant colors, deep blacks, and bright whites.

3D TV continues to die a slow death, even though some manufacturers are still trying to convince us we need it. Think of 3D as Three Times Dead.

Bottom line, OLED is better than LED, 4K is amazing when you can see 4K content, both 4K and 8K are Ultra High Definition (UHD), both cost twice as much or more than HD, both require faster internet to be useful. Since there is little 4K and no 8K content, people who buy theses TVs are stuck explaining the picture deficiency and Ultra High Cost to guests. When content arrives, these TVs will be awesome and, by then, the price will be much more affordable. Last thing, when it comes to TVs, bigger is better, OLED is much better, 4K is awesome, but too expensive, for now.