Q: I bought your book and read the section on how far to sit from an HDTV. According to your example, I should sit closer to a 53-inch HDTV than the distance recommended by another site suggests. I realize that you take the resolution of the HDTV into account and the others don’t. Does that explain the difference between your recommendations and theirs?
A: First, let me say thanks for buying my book. And while you included a link to the site you referred to for the conflicting viewing distance recommendation, I have omitted it here because there’s no need to pick on any one site. There are many sites that make similar recommendations, and I suspect that many of them are based simply on on information available elsewhere, such as CEDIA’s tables.
Many of these sites — if not all — do not explain how they calculate their recommendations. As a result, it is difficult to evaluate them or explain the difference from my results. But clearly, resolution is a major difference. Think about it; a full sheet of a newspaper and a travel poster are about the same size, but the recommended viewing distances for each are very different. If a display is made up of dots, then there is a distance at which the human vision system can’t distinguish between the dots. At that point, you won’t be able to tell the difference between a higher-resolution (and more expensive) HDTV than one the same size with lower resolution. I think it’s intellectually lazy to ignore this factor.
Also most sites — if not all — give you the information backwards. They’ll tell you how far to sit from a 42-inch HDTV. But most people aren’t starting with the display; they’re starting with a room that already has a viewing distance. So in my book, I have you measure the distance, multiply it by a single number, and you get the optimal size display for the room. Simple and easy.