Showing posts with label UHD. Show all posts
Showing posts with label UHD. 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 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.