Nope, it’s actually a LOT more than “just a filter.” And 24 progressive isn’t going to guarantee you an “HD look” either. There are lots of things that can be done with SD, lots of things that can be done cheaply in some form of higher definition, but a filter or special effect isn’t going to accomplish the pristine pimples and nose hairs, peach fuzz and dew look of perfectly focused, well-lighted high definition footage.
People research and test to find something they can live with, and a whole ‘nother set seek ways to “trash” the HD look so it isn’t quite so crisp and pristine – the quality, class and architecture of what winds up on the screen (outside testing for the numbers using appropriate equipment) is totally subjective. Beauty is in the eye, or attitude, or school of thought, experience, or learning of the beholder.
None, however, are going to find high definition’s plane of quality apparent in a filter or digital post-production workaround IMHO.
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