No harm in Hz?

Remember the days when TV only meant one thing? After the advent of color, there really wasn’t much else to distinguish TV. We were blissfully unaware of anything beyond. With advances in video and broadcast technology, the idyllic existence slowly crumbled away. First came the concept of interlaced versus progressive. At first it took a bit to get one’s head wrapped around the concept. What do you mean the TV only draws half of the picture at a time? Then came the full flurry of ATSC. We went from TV to 480i/p, 576i/p, 720p, 1080i and finally 1080p. But wait there was more, there’s also 24/30/60 fps (and those peculiar 23.97/29.97/59.94 rates as well or 50 fps for our European readers). Did I mention there’s a difference between a frame and a field?
Still here? Given the near instantaneous proliferation of formats, is it any wonder that the average consumer can be so overwhelmed? The problem now is the industry seems to have moved beyond trying to educate the consumer to preying on their ignorance.
If one looks at the source material it simplifies matters somewhat. Source material is typically recorded at 24/30/60 interlaced or progressive frames or fields per second. Take a quick look at commercial broadcast and recording equipment. It becomes quickly apparent, that despite vast differences in interfaces and bit-rates, the basic frame rates don’t change. That camera broadcasting the Flames and Blackhawks is only capturing 29.97 frames per second (59.94 fields per second or 60i). So is there a real benefit to seeing the same frame as many as 8x (in the case of 480 Hz)? There certainly no interpolation to generate new frames of data so why?
That it’s largely a marketing (and partially a technical) benefit becomes apparent when one looks at the underlying screen technology most often touting ultra high refresh rates. Nearly without fail you will find high refresh rates being touted for one screen technology, liquid crystal display. The elevated refresh rates are used as a means to mitigate ghosting or motion blur. While vast improvements have been made in grey-to-gray (GtG) transition rates, the still lag those possible with plasma or CRTs. Some manufacturers are even inserting blank frames to boost contrast and/or address the ghosting. While one can’t argue with the novelty in addressing technical limitations, the problem arises with claims of smoother replay of fast moving objects on screen. One just needs to take a look at flyers from your favorite big-box electronics store.

Andrew Yang

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