It’s no argument that the video side of A/V has been the most active the past few years. But I will go out on a limb here and say that a large portion of it is hype. Since the huge leap from CRT to flat panels, whether LCD or plasma, or VHS to DVD most improvements have been marginal. 10ms response times to 5ms response times, 60Hz refresh rates to 120Hz refresh rates or even 1080i to 1080p, none of them are truly ground breaking, then came along “4K”. What is 4K, where did it come from, who, what, when, where and why?
To the surprise of most it’s been around a little while but it has followed suit with advancing technologies and trickles down slowly from the commercial industry to the consumer market. The major production studios agreed upon the 4K format years ago and there is some argument as to the number of films that where originally filmed in true 4K format. It is known that only one so far has made it all the way to market via Blu-Ray and that is Spider-Man 3.
Nonetheless the next time your buddy, who just had to be the first one on the block to have one, is showing off his shiny new flat panel with the “latest & greatest” technology. You can quietly laugh inside knowing that he shelled out a whopping premium price tag for something the industry is already preparing to leave behind, filed right next to Beta! Okay maybe that’s a little extreme but if it gives you that little extra satisfaction why not!
Apparently someone at Sony took notice of 4K and decided it was time to get serious and in October 2005 the Sony SRX-R110 and SRX-R105 became the world’s first commercially available 4K projectors, with devices delivered to Landmark Theaters, the National Geographic Society and Sony Pictures Entertainment. What Sony has done with this format and the projector technology used to reproduce it is nothing short of astounding. This is the next VHS to DVD epiphany!
In the metric system, “K” is short for kilo, the prefix for 1000. But in the binary system of computers, “K” equals 2 to the tenth power, or 1024. In the jargon of digital cinema, “4K” refers to an image that’s 4 x 1024, 4096 pixels wide. Sony 4K projectors achieve a resolution of 4096 pixels horizontal x 2160 pixels vertical. This is slightly more than four times the pixels of the highest high definition TV specification (1920 x 1080). You can think of 4K as delivering four times the pixels per square inch. For example, if you held a credit cared up to a screen 27 feet wide, the card would be covered by over 1,000 pixels. And each pixel would be the size of the letter “E” in the word LIBERTY on a US quarter.
4K content has originated from scanning 35mm or 65mm motion picture film, from computer animation and 4K digital cameras. For Digital Cinemas, this content is typically played from a growing selection of servers that are compatible with the 4K signal.
First, with SXRD the gaps between the pixels are unusually narrow in proportion to the live image area. Roughly 92% of the image is live, with only about 8% devoted to gaps. Then SXRD 4K projection presses this advantage further still, with pixels that are roughly ¼ the area of HD pixels at a given screen size.
With the ability to display one, two or four simultaneous HD video feeds at full 1920 x 1080 resolution, the Sony projectors enable a new generation of mission-critical video monitoring.
Pixel pitch, measures the center-to-center distance of adjacent pixels, taking into account not only the size of the pixel itself but also the gap between the pixels. Sony’s 4K SXRD panel has a pixel pitch of just 8.5 micrometers. In comparison a human hair is roughly 70 micrometers thick. It’s this 8.5-micrometer pitch that enables Sony to deliver 8.8 Megapixels on a device not much bigger than a competing panel that delivers just 2.2 Megapixels.
In the case of the 4K panel, the distance from the center of one SXRD pixel to the center of the next is 8.5 micrometers, while the inter-pixel gap is just 0.35 micrometers!
In practice, response time decreases dramatically as you reduce the LC layer thickness. So reducing the panel thickness by 50% means cutting the response time by more than 75% for a response time of <2.5ms.
4K is now supported by media servers and external image processors. And 4K is an accepted part of the Digital Cinema workflow from acquisition to postproduction to distribution and exhibition.
by Jason Levert