Michael, My friend you are
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Michael,
My friend you are trying to change ‘apples’ to ‘oranges’. You’re trying to make a much lower resolution format of video look ‘better’ on a much higher video format TV. Not gonna’ happen.
That said, depending on what the original tapes were shot on, what kind of condition they’re still in (analog tape degrades after a number of years and how many times have they been viewed are major factors) will decide how good a ‘quality’ image you have to work with. You could try to ‘remaster’ the video in Vegas Pro to a certain degree with color correction tweaks but unless it was shot on a pro Hi-8 or Betacam-SP camera, even ‘tweaks’ aren’t going to help much.