Live studio broadcasts and sporting events in HD are excellent sources to compare to SD channels. Facial hair, individual blades of grass in golf or baseball, and other images that appear to be 3-dimensional or photo quality are typical examples of HD images. SD images by comparison could be described as a little blurry or fuzzy.
You can find the resolution setting in your TV settings menu. The resolution listing should be in your owner’s manual. [3] X Research source The “i” stands for “interlaced,” which means the image on your screen flickers between every other line, and the “p” stands for “progressive,” which means the image constantly uses every line on the TV screen to display the image. [4] X Research source
HD and SD screens have different aspect ratios, so HDTVs sometimes distort an SD image to make it fit the screen. SD screens normally use the 4:3 aspect ratio, while HD screens normally have a 16:9 aspect ratio.
DVDs may look higher-quality when played on HDTVs because they’re being up inverted to play on the HD resolution. However, this still does not qualify as HD. [6] X Research source
For example, if the HDTV is capable of up to 720p, you shouldn’t select an input greater than 720p. The same goes for 1080i or 1080P sources.
All HD inputs are single connectors, so an easy way to tell if the input is meant for SD only is to check if there are multiple connectors. For example, “composite video and stereo audio" inputs have three components in different colors.
Some older devices may also allow you to use an analog component video cable, but HDMI is generally a better choice because it is more universal and used by all newer devices. HDMI cables are very common and extremely affordable–you can purchase one for less than $5. [11] X Research source
