A key factor to consider when determining the size of the screen is the viewing distance. As a general rule, HD TVs larger than 65" require a minimum viewing distance of 9 ft. For Ultra HD (also known as 4K TVs), the viewing distance can be halved. With that factored, pick the largest screen size that will fit comfortably in your budget and the area you plan to place the TV. The sweet spot today, considering price, performance and the typical living room, is between 55 and 65 inches.
Quick Tips Buying Guide
HD TV vs Ultra HD/4KResolution is an important factor in your buying decision. It describes the number of lines (and ultimately the total # of pixels) that create the image. The greater the number, i.e. 720p, 1080i and 1080p for example, the better the image.
The letter following the number describes the type of scan used by the TV to display the picture. A "p", short for progressive, means the picture is created in a single pass, i.e. lines 1, then 2, then 3 and so on. An "i", short for interlaced, means the picture is created in 2 passes, first it paints the odd number lines, 1, 3, 5 etc, then it repeats the process and paints the even, 2, 4, 6 etc. In general, progressive scans look sharper and more defined than 1080i, particularly during scenes with a lot of fast motion and the differences are less discenable on smaller screens.
High Definition, generally describes a resolution of 1920 pixels in width and 1080 pixels high, for a resolution of 2,073,600 pixels (i.e. 1080 x 1920 pixels).
Ulta High Definition TV (UHD TV), also known as 4k TV, doubles the number of pixels wide and high, to 3840 x 2160. A UHD TV has the ability to display greater detail than a 1080p HDTV. Images appear a bit sharper, with smoother lines on the edges of objects—depending on your viewing distance.
Note: the source of the content needs to be in the UHD format for you to get the full benefit of your UHD TV. At present (end of 2016), there are no 4K broadcast or cable channels, and there are only a handful of streaming options available. Netflix and Amazon and specialty services such as UltraFlix, Dish Network and DirecTV are rolling out 4K download services. While Ultra HD sets can upscale existing HD content, the results can be mixed and do not look as sharp as original 4K programming.
What is HDR?
HDR, short for high dynamic range, is a new feature in TVs designed to show a more realistic image, with more contrast, brightness and color. HDR expands the ability to display a wider and richer range of colors, much brighter whites, and much deeper, darker blacks. HDR content preserves details in the darkest and brightest areas of a picture that are lost using current standards, which allows for more natural, true-to-life colors that are closer to how we see them in real life.
The feature over time will be marketed with different names, so don't be confused.
- Ultra HD Premium is the name being adopted by UHD Alliance, an industry trade group. Dozens of companies are supporting this basic minimum specification for HDR compatibility, so the term "Ultra HD Premium" will become more prevalent.
- Dolby Vision is another version. It is a more demanding version of HDR. In theory, a Dolby Vision set has to meet a stricter set of criteria to display HDR content.
The refresh rate, describes how many times per second a picture is refreshed on the screen. In general, the higher the rate, the better the viewing experience.
Measured in hertz (Hz), the standard refresh rate is 60Hz, or in other words, the picture is refreshed 60 times per second. For content that has fast motion, such as sports, a 60hz refresh can make things look blurry or jerky. Increasing the refresh rates helps to overcome this, and smooth out the picture. Some TVs have refresh rates of 120 Hz and in some cases up to 240 Hz.
Note: Don't be fooled by terms like "effective refresh rate". Look for TVs that provides the actual frame rate. A "120 Hz effective refresh rate" is actually a 60 Hz refresh rate.
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