OK, I realize this is a fairly dumb and unimportant question, but it's been bugging me and I'm sure someone here has an answer. I noticed recently that on Olympus cameras the square aspect ratio is referred to as "6:6", while Panasonic labels this "1:1". Obviously these are both the same thing, but 1:1 seems like a more intuitive description. I presume there's some (historical?) reason why Olympus uses the 6:6 terminology, but it's lost on me. Anyone know what the reason is?