Showing posts with label HDR. Show all posts
Showing posts with label HDR. 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.

Jul 29, 2016

TV Types

High Dynamic Range (HDR) is now entering the market, traditional light emitting diode (LED) TVs are benefiting from the extra performance. If you watch movies with the lights off HDR is fine, but the best HDR-equipped full back lit LED TVs can also look good in a bright room.

Among LED TVs, there are two backlight types: Direct LED (full-array) where a large back-light shines through the whole screen, and edge-lit where lights emit from the edges.

Organic light emitting diode (OLED) TVs tend to shine, especially when the lights are off. This is because every pixel emits its own light. OLED is still the best, but if you want a TV above 65 inches you likely will be choosing an LED TV, unless you have a spare $30,000, which is the current cost of large OLED TVs.