Your best bet is to read the manual - shocker.I've always disliked rear projection sets. No matter what it's called, it's rarely on by default - even when watching 1080p24 from Blu-ray which never has garbage on the edges! - so you'll have to find the button on the remote called something like format or P.size, depending on the brand. Of course each manufacture has its own name for this mode like Samsung who sometimes calls it Screen Fit, and Pioneer called it Dot by Dot. This simply means that every pixel in the signal is displayed by a single pixel on the display. When an image is displayed properly, it's sometimes referred as 1:1 pixel mapping. In the meantime we're just happy that most TVs have a way to turn it off. In a perfect world broadcasters would mind their signal and ensure every pixel was worth watching, then TV manufacturers wouldn't feel the need for overscan - or at least we hope. These are the same screen shot, one is presented with overscan, one isn't. The source of the problem is that broadcasters expect the TV to crop the image so they don't mind putting garbage on the edge - like a misc yellow line on the left or black and white dots show in the images below. So if CRTs are dead then why do we still have overscan? This is where the bad news comes in, but the short answer is because it used to be there. So instead the image was overscanned which resulted in some loss of picture but maintained quality for the center of the image - the part that matters most. The problem with CRTs was that a limitation of the technology was its inability to accurately reproduce images along the edges of the tube. The term comes from the days of CRTs when the scan lines that drew the image literally scanned over the edge of the viewable part of the tube - PC users were all too familiar with the small print that a 21-inch CRT PC display proclaiming that it was actually 20-inch viewable. If you take a picture and cut off an inch from each edge and blow it up to the original size, then you'd effectively be overscanning. The easiest way to wrap your head around overscan is to forget about the word for a second and think of cropping an image. A test pattern with overscan markers on the four edges.
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January 2023
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