Quote:
Originally Posted by NewVista
This should be a no-brainer yet only movie people use 4k cameras!
Always wondered why HDTV cameras 2k? Naive?
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Depends on the tradeoffs when you're making the sensors. In the early days of CCDs they were struggling to make them work at all, you got as many pixels as you could reasonably make work at all. There are also 2 tradeoffs that may well be fundamental. For a given image size on the chip, if you have more pixels each one is smaller and hence collects less light. Also the fill factor, the fraction of the chip's surface that's sensitive to light, goes down. While a theoretically ideal sampler has infinitesimally small pixels it would also have infinitesimal sensitivity. Hence the sensor designer strives to fill as much of the space as possible with pixels and leave minimum space between them.
Image size is important. For cine camera replacement you want to be able to use your existing stock of 35mm prime lenses. Hence the sensor size needs to replicate 35mm film area. For TV the sensors are smaller.
I haven't looked at what size sensors Super Hi-Vision uses but the fundamental resolution is about 8k x 4k. I saw a demonstration a few days ago at BBC Broadcasting House, some recordings from the Olympics. NHK and BBC have worked together to televise parts of the olympics on this new system. Only 3 cameras so a refreshing return to old fashioned production values, lots of lingering wide shots, minimal pans or zooms. You don't need closeups when you have that much resolution available. From my seat, about 30 feet from a 25 foot screen the pictures were perfectly detailed and flawless, even under difficult lighting conditions such as fireworks.
The pictures were also being relayed to Bradford, Glasgow, Washington DC, Tokyo and Fukushima so some of you may have had a chance to see them.