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SVM  --  scan velocity modulation -- as with "enhancement" done with the sharpness control -- emphasizes the vertical lines by adding an opposing black or white edge to the right of all existing vertical-line edges, including curved ones.

Not all Sharpness controls involve enhancement, BTW. Some are strictly picture dulling agents -- video filters -- for getting rid of graininess and crappy cable noisiness -- or for lack of a more dignified term -- cable gluk.

This was the case with the old, original (state of the art back then) Advent projectors. They called it "Detail", and their manual specifically directed the viewer to turn this knob all the way UP if you already had a clean, crisp video source. This got the video filter to be completely bypassed, and thus out of circuit.

You'd do this with sources like the old analog big dishes, which were the only state of the art consumer source back then.

Tho I gotta tellya, even today a finely set up and precision-aimed roof antenna, with just the right amount of reception gain and absolutely no multipath signal reflections, produces a stellar picture also, head and shoulders better than cable ever has. This is made even more evident if you've seen the incredibly fine-detail picture OTA - off the air - HD broadcasts are capable of today, bypassing the detail potential even of DVD.

Most sharpness controls are both, video filters on the left half of the bar graph and enhancers on the right half of the Sharpness control. In which case the correct position is in the MIDDLE, cancelling both. Strictly video filters need to be all the way down to the left side.

Watch those last 2 notches to the left, tho. Many video filters double their effect at the left hand endpoint, leaving a REEAALY dulled-out picture.  Sometimes on those the best position is at one third, where half would be the middle. You have to play with it.

What SVM does, is cause BIGGER outlines. Which is fine if you're 15 feet away from a 35" or smaller direct view -- the Mit 35" DV used SVM quite effectively, since everybody was used to watching a direct view TV from a significant distance anyway. Same with all direct views, except that Sony takes it to a fault on their Wega series, and the picture looks a lot better when you are in Movie mode, I believe it is, where the SVM is cancelled while in that mode.

However, it obliterates detail when done on a 50" or 60" -- or bigger -- RPTV. That is, unless this TV is not calibrated to begin with, you are sitting 20' away from a 50" TV, and you want crisper outlines without having to pay for a calibration, in which case it helps. It will give you crisper BIG outlines, but will make it impossible to have extremely fine detail.

If you're sitting 20' away from a 50", that's no problem. You won't be seeing fine detail anyway, and if that is what your viewing distance choice is, you're not looking for fine detail anyway.

If you want to really get in there and increase your suspension of disbelief by wrapping your peripheral vision with more picture by sitting closer -- which a calibration grants you the ability to do -- you don't want SVM. The finer the detail, the more definition you have; the more depth you have in your picture. SVM stretches the vertical lineage to the side, then adds a false secondary reversed -- negative -- image to make up for it. Fine detail is not their primary concern, when they design in SVM to a television. Making outlines show up better from a distance is.