Why is NTSC 4:3 preset 720 x 486?

I’m just curious about the “486”? Shouldn’t it be “480”?

More than you ever wanted to know: http://forums.creativecow.net/thread/8/1093119

TL : DR: Some NTSC gear uses 720x486, DV uses 720x480. (Yes the pixels are non-square either way.) The square pixel equivalents are generally accepted as 640x480 for 4:3, and 853x480 for widescreen (854x480 is sometimes used to keep even numbers on both sides, IIRC this can improve compression efficiency).

Oh, and widescreen NTSC is still 720x480/486, the pixels are just “flipped sideways”.

Have you learned about 29.97fps yet? :p:eyebrowlift2:

OK thanks for that, I never heard of this “486” thing before? Reading that thread, it seems it is not too common, and “480” is more the broadcast standard? I guess for NTSC mpeg2 output from Blender I will stick to “720 x 480”.