Fine Art - 16:9
Since 2009, it has become the most common aspect ratio for sold televisions and computer monitors and is also the international standard format of HDTV, Full HD, non-HD digital television and analog widescreen television. (Wikipedia). So if we present portraits in this ratio we will automatically associate it with filmstills. Or how our brains and our way to look at images has been changed by the filmindustry.