Originally Posted by Ron Jones
Yes it does matter. A 24Hz refresh will cause noticable flicker in the image. Many people will also object to the flicker at 48Hz and at 72Hz it becomes flicker free for most people. For example, some of the new Panasonic 1080p plasmas can display a 1080p/24 input at 48Hz and I can see the flicker (also reported in a recent magazine review). Even movie projectors display each frame of the 24 frames per second film multiple times to reduce the perceived flicker in the image.
My understanding is that SXRD, DILA and LCD all show a frame permanently until something changes. There is no black time between frames like there is on scanning devices like CRTs.
So for most devices of this kind, there will be absolutely no difference
between 24/48/96 or 120hz.
However now that we're up to 120hz, some companies have started to try and add processing algorithms to try and improve 2 things...
1) One thing is that our eyes don't like this sample and hold effect and see motion smear. This is different for different people (a bit like rainbows are) but it can be quite irritating.
Sony has introduced 'Black Frame Insertion' so that in between each real frame of movie, there is now a black frame (in fact they show the black frame at a frequency of 48hz, which is the same as a commercial film-based theater). Our brain prefers motion seen like this and sees less motion smear. The flicker might bother some people, but not me.
2) The second issue is that 24 frames isn't actually very much and some companies are trying to add new interpolated frames inbetween the old ones in order to smooth out motion. The classic scene I can remember seeing 24fps judder on is when Titanic leaves the harbour. You could see the bow of the ship flickering/juddering as it travels across the screen.
Sony call this MotionFlow and some people like it for everything, others like it just for video-based 60hz material like sports, etc. Others don't like it at all.
Panasonic and Epson have both included this in their next products. But I haven't seen 'Dark Frame Insertion' mentioned as yet, which is a shame.
Edit: By the way - I don't think the HW10 includes these Sony features, but I may be wrong.
Edit 2: frame interpolation also helps with the motion smear associated with sample and hold devices, but some don't like it's side effects.
Hope that helps