That is a such a simple formula, I never woulda thought of doing it that way! Nice! It also confirms a handy rule of thumb I discovered: take your eyeball-to-screen distance and divide by two. That will give you a ballpark figure of what size (diagonal) screen to look for. Worked great for me: I'm 100 inches away from my 50-inch TV. For SD, it's a tad soft, but for HD, it's just a wee too small -- a good balance, since I watch both.
cheers,
supervij
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