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Scan Velocity Modulation (VSM or VSM)

S.V.M. or Scan Velocity Modulation also referred to as VSM affects all luminance transitions as the electron beam scans the CRT from left to right. SVM causes the electron gun to slow down when scanning bright objects. It therefore distorts brightness and geometry for the sake of "improved" contrast and sharpness. It's about as useful as "auto-color". Manufacturers add these worthless items to sets for the same reason they max-out the "blueness" of the color white. That is, to make it stand out on the showroom floor and look "better" to the uninformed casual viewer.

Some feel that disabling this feature provides a much truer picture.  Examine the images below:

The HDTV text on the left prominently shows the effects of modulation.  The top and bottom halves of the text are not the same width even though they should be.  It also exhibits overshoot or ringing as evidenced by the white outline (shown here as light gray) around the black text.

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