View Full Version : The need for 4K or why 2K is not enough for theatrical projections (Sony white paper)


Carlos Molina
February 4th, 2011, 04:15 PM
"Does 4K really make a difference? 4K digital projection in the theater environment"

(Sony white paper, 2nd edition, May 3, 2010)

http://pro.sony.com/bbsccms/static/files/mkt/digitalcinema/Why_4K_WP_Final.pdf

Ben Fullerton
October 16th, 2011, 11:08 PM
That was quite the lengthy read, and I skimmed it quite a bit. But it sounded like they were saying that 4k is worth it, which is an interesting position for a company that just released cameras targeted to compete with RED, while holding onto a 1080p format. I would suppose they make projectors or something that they are trying to sell, but still odd that they would have that mentality when it comes to projecting, but not when it comes to acquisition.

Or did I totally misread that article...?

Arnie Schlissel
October 17th, 2011, 12:33 PM
Maybe it's because Sony's introducing a 4k home theater projector at the end of this year:
Sony Electronics News and Information (http://news.sel.sony.com/en/press_room/consumer/television/release/60811.html)

Brian Drysdale
October 18th, 2011, 03:50 AM
Most productions are for 1080 distribution, the 4k makes sense to give more in the theatres than you can see at home through HDTV. This follows from the days when cinemascope and 70mm were brought out in the cinemas to compete with television in the 1950s.

4k home cinema would be a follow on to the systems that people have had for a while, although you'll need the film distributors on board first with an agreed release 4k format for home use.

David Chien
October 22nd, 2012, 09:48 PM
http://www.nhk.or.jp/digital/en/super_hi/NHKsuperHiV_english.pdf

There is a need for 33K, or why 4K or 2K isn't enough, IMO.

I've seen a 4K monitor hooked up at Siggraph this summer. Nice, but no cigar! You can still see the pixels on the huge 50+" display, and the macroblocking, artifacts, etc. are still quite visible. Not 'impressive' considering the $10+K price of the monitor alone.

Keep in mind that 2K = 2MP, 4K = 4MP equivalents in the photo world. (H x W = MP or K)
Remember when cameras ONLY were 2-4MP and you tried to print a BIG poster? Didn't look too good, right?

That's because when it comes down to lp/mm, 4K is definitely not enough to make the case for expensive, new 4K cameras or TVs just to replace 2K gear we all have.

http://www.sony.net/Products/SC-HP/cx_news/vol69/pdf/imx144cqj.pdf
This is where Sony is truly looking forward and thinking to the 33K world by releasing their 12K @ 35fps sensor (and cameras & camcorders next year).

Just to blow a photo to wall-size requires well above 10MP for a sharp, crisp, detailed image, and you can't expect a 4K video to look much stunningly better than 2K at 50+ inches. I certainly wasn't impressed at Siggraph.

Alen Koebel
February 5th, 2013, 04:02 PM
http://www.sony.net/Products/SC-HP/cx_news/vol69/pdf/imx144cqj.pdf
This is where Sony is truly looking forward and thinking to the 33K world by releasing their 12K @ 35fps sensor (and cameras & camcorders next year).

Looks like a nice chip. Do you know yet which models will use it?

Shaun Roemich
February 6th, 2013, 12:15 PM
Keep in mind that 2K = 2MP, 4K = 4MP equivalents in the photo world. (H x W = MP or K)
Remember when cameras ONLY were 2-4MP and you tried to print a BIG poster? Didn't look too good, right?

Your math is in error. 4k does NOT mean 4 million pixels on screen. It is the WIDTH of the image in pixels (4k = 4000 or 4096, although sometimes 3840), approximated of course to make things complicated...

4K resolution - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/4K_resolution)

4K equates to a MINIMUM of 7 million pixels (Cinemascope crop) and usually in excess of 8 million.

Glen Vandermolen
February 6th, 2013, 01:38 PM
Here's another take on 4K:

4K Has More Challenges Than Cost (http://news.doddleme.com/equipment/4k-has-more-challenges-than-cost/)

Shaun Roemich
February 6th, 2013, 03:50 PM
Some hyperbole in that article Glen:

"Then there’s the issue of bandwidth, which we’ve discussed before. According to Chen, in order for viewers to enjoy 4k as broadcast or streaming, they’d have to have enough bandwidth to handle the 8.91 Gb/s pipeline. And at that rate, most Internet data caps would be eaten up in less time than it takes to watch a single episode of The Big Bang Theory. Not going to happen since Internet providers are refusing to update their out of date business models."

We aren't watching 1080P at 1.5Gbps right now, even though the 4:2:2 data stream certainly is that. Nor are we RECORDING 1.5Gbps in virtually ANY application (yes, there are uncompressed recorders out there but almost all HD production is done at SOME level of compressed at acquisition, whether h.264, XDCamEX or ProRes).

Netflix streams up to 5.18MBps (or 41.44 Mbps) for HD content according to this article:

The Escapist : News : Netflix Takes Charge of Data Delivery (http://www.escapistmagazine.com/news/view/118040-Netflix-Takes-Charge-of-Data-Delivery)

This is approximately 36:1 compression versus uncompressed 1.5Gbps.

To maintain the same level of compression on the 8.91Gbps 4k signal, we'd see data rates in the range of 250Mbps.

John Wiley
February 7th, 2013, 12:50 AM
http://www.nhk.or.jp/digital/en/super_hi/NHKsuperHiV_english.pdf

Keep in mind that 2K = 2MP, 4K = 4MP equivalents in the photo world. (H x W = MP or K)
Remember when cameras ONLY were 2-4MP and you tried to print a BIG poster? Didn't look too good, right?

That's because when it comes down to lp/mm, 4K is definitely not enough to make the case for expensive, new 4K cameras or TVs just to replace 2K gear we all have.



Actually, when talking in cinema terms, only the horizontal lines are referenced. Perhaps this has something to do with the fact there are so many cinema "standards" (1.85:1, 16:9, 2.35:1, etc) so it is a way of comparing them all on a single constant.

So 4K at 1.85:1 is a little over 8mp. 2K is just slightly larger than 1080p HD.

That 33K you mentioned would be somewhere in the ballpark of 530 megapixels, which seems just a bit excessive, even by still photography standards.

Even all the talk of people wanting 8K has me scratching my head - who could possibly need/handle 32mp video?