Still trying to understand all this, John. When you feed a 480 signal or, for that matter, a 1080 signal to a 720p HDTV, isn't the signal converted (scaled?), by the TV, to the TV's native resolution (i.e., in this example, 720p)?
Actually, we're joking (sorta) about needing seating with wheels or rails because the two articles disagree about the optimal seating distance for a given set of any resolution. That's why I said:
Quote:
...if you compare the formula in the article Nick provided to the formula in the article I provided, for a 56"/1080p set, one recommends a viewing distance of 7.2', and the other 11.43'.
HOWEVER! I must stand corrected (while remaining seated). The formula in my article was meant only for 720p sets not 1080p. With that in mind, for a 720p set, the formula in my article recommends a seating distance of 11.43' and the formula in Nick's article recommends 10.8', which is only a difference of about 8.5 inches. So, actually, the formulas don't disagree to any significant degree. Apologies to all. 
