As Dave explained it to me, since the banners are prominent, front and center for 24 hours at the very top of the page, they must be framed right and sharp and in focus as much as possible. Using blurry images or poorly shot photos shows ATP in a very poor light and we can't afford to do it.
Since the ATP logo pushes the banner over and then puts the logo on, only the first 1/2 of most banners are visible to most viewers so try to select a photo based on where the subject will end up being.
As it says on the banner submission page "The image must be exactly 150 pixels high and at least 1,200 pixels wide. Please only upload banners from your very best, sharpest and most colorful images."
