I quote the following sentence from http://en.wikipedia.org/wiki/8_mm_video_format which reads: "Both Hi8 and SVHS were officially rated at a luminance resolution of 420 horizontal TV/lines (566x480 in today's digital terms), a vast improvement from their respective base-formats of 240 lines and roughly equal to laserdisc quality." I fail to understand how does "420 horizontal TV/lines" become 566*480. First of all, I understand that "horizontal lines" are counted up and down along the Y (vertical) axis, so it should only affect the 480 vertical resolution. Are the missing 60 lines eaten up by overscan or something? More importantly, what is a reasonable resolution for digitally capturing Video8 and Hi8 sources? 640*480 for the latter?
Keep in mind the "Horizontal resolution" is the horizontal lines of resolution over the same video height, that is, 1:1. A standard TV is 4:3. So, for example, DVD's 540 lines of Horizontal Resolution x 1.33 come out to approximately 720 pixels across. Calculating backwards, 566/1.33 = 425, which is roughly the Horizontal resolution of Hi-8. So that's likely where the 566 x 480 comes from. If I was capturing SVHS or Hi-8 I wouldn't quibble over the finer points, I'd slam it at 720 x 480.
