All content on Netflix is presented in its original aspect ratio, which for many titles, is 4:3. Unfortunately, most people view Netflix content on widescreen televisions, leading to black bars on the sides the image during playback.
Many Netflix playback devices (for example, the Playstation 3) do not allow you to set content to play in 16:9 widescreen mode. The workaround for this is simple - set your television to "16:9" or "widescreen" or "full screen". Typically you can change this on the fly with the "format" or "aspect" button on your remote control.
You might be thinking "well - obviously" - but many people do not realize this! You'll have to set it back to its original setting when you are finished watching. Until Netflix updates its playback software to change aspect ratio on the fly, this is the simplest solution.
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