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The Future of Digital Cinema
An anonymous reader writes "The New York Times recently had an interesting article on the future of digital cinema. The article talks mainly about the Digital Cinema Initiatives consortium (formed last year by a group of seven major studios) and its work towards establishing a set of standards for theatrical digital projection. DigitalCinemaMag also had an article back in February about the consortium's efforts which included a few more technical details."
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I thought the 'Star Wars' digital showing looked very bad.
I saw it at Mann's Chinese theater with a digital projector and I thought it looked awesome
"I can not bring myself to believe that if knowledge presents danger, the solution is ignorance" - Isaac Asimov
I've been working with some of the digital cinema technology for the past couple of years. I even worked with the University of Southern California's Entertainment Technology Center which is mentioned in the article. The device we were using operated at 60fps normally. It can run at other rates as well depending on the task. I'm not going to make an quality comments since I was using the system for "non-cinema" work, but the tech is there for increasing the frame rate.
Better framerates are on the way. Check this out for more info on higher quality HD video and movies.
The IPCC has purposely engineered a massive scientific fraud.
1. I was one of those "grain sniffers". I was at a demo of an upcoming 11,000 lumen high res projector standing a few feet away from the screen, and I couldn't see any pixellation. The brightness and sharpness was astounding. Plus this project runs Linux, decrypting the image on the fly.
2. Image quality depends a lot on the projectionists. I sat in the projection booth of a megaplex for a week a while ago and saw three different projectionists opening up in the morning, and while all of them cleaned the lens, film gates and transport mechanism on the projector, not one of them cleaned the glass at the front of the booth. You could see dirt and finger marks on the glass even before they struck the lamphouse. I asked one of the projectionists about it, and he was pretty contemptuous of the type of audience they got at that plex and the type of low brow action-heavy movies they showed there. I got the impression he wanted to be at some arts house, and maybe if he'd had more respect for the audience he would have worried more about their experience. On the other hand, I work with another projectionist who is meticulous about every aspect of the showing.
The next Cmdr Taco duplicate will be ready soon, but subscribers can beat the rush and see it early!
OK, you've piqued my curiosity. Just how much storage?
Let's start with a two-hour film shot at 60fps with 2048 lines of vertical resolution, 48bpp color, and a 2.35:1 aspect ratio.
If we round off the screen resolution to 4800x2048, that's 9.375Mpixels, 56.25MB/frame, 3.3GB/second, or about 23TB for a two-hour film, uncompressed. I don't know much about video compression, but it sounds intuitive to me that you could get 5:1 compression and still get an OK picture, which works out to about 4.6TB. Let's round that up to 5TB for a good back-of-the-envelope guess.
By the time movies start coming out in a format like this (someone still has to build the cameras and the post-production infrastructure), a single hard drive should be able to hold that much, but that still sticks you with mailing physical media to the theaters. I'll leave it to someone else to do the math as to whether multicast distribution over a private network would be feasible.
I think in the meantime, we should follow Roger Ebert's recommendation for improving the viewer experience. Switch to 35mm film at 48fps. The projector mods are much less expensive than digital projectors,and they're backwards-compatible with conventional film. In its current incarnation, digital is a boon to the studios at the expense of the theaters.
(Side note: Showscan, 70mm film at 60fps IIRC, was the coolest thing I've ever seen projected anywhere.)
The biggest technical hurdle with high resolution digital movie cameras is moving all that data from the CCD to the disks. According to one friend who is working on such a camera, they are using several independant PCI busses feeding large arrays of disks.
When you think about it, it's remarkable how much bandwidth analog film has - you can store the equivalent of 10s of megapixels in full color in 1/250th of a second and be ready to shoot the next frame as quickly as you can move the film, compared to the 4 or 5 seconds my 4 megapixel camera takes to store an image.
The next Cmdr Taco duplicate will be ready soon, but subscribers can beat the rush and see it early!
I firmly believe much of what people find lacking in "digital film" is the noise and grain - much like digital audio. Of course, the technology is very young - digital video is relatively where digital audio was around 1985. Still, taking a "clean" film and adding a bit of "grain" richens it considerably.
Anyway, let's see you do a complete 90 minute feature in one very long take while hauling around a film camera...
When comparing pixels to film, the actual pixel resolution is only part of the equation. Yes, standard color CCD arrays use an offset-overlay technique to interpolate more resolution in the final image than any of the single color channels has. The exception to this is the Foevon chip, which has full color in every pixel, and the very high end systems you mention above.
The huge, HUGE advantage of digital imaging that you have not mentioned is grain. The spatial resolution (or how much detail is actually in the picture content) is actually very poor in 35mm, especially in less-exposed areas. If I accidentally underexpose my digital image by one or two stops, I can use a level adjustment to recover a near-perfect image with very little grain, and plenty of detail in even the darkest areas. If I try that with a 35mm film scan, it will be extremely grainy, even from a very low ISO film. The reason 35mm gets by is that at full frame from a reasonable viewing distance and at a correct exposure, the softness, gamma, grain and falloff present a nice pleasing picture.
In every day practical use, I find that a 6 megapixel standard CCD (not foevon) producing a 3k file has better detail than the average 35mm image. Downsampled to 2k and it's an extremely sharp, excellent 2k image. Right now I even have a 3 megapixel (2k) image from an older camera on a billboard just outside of town, it's about 15 feet across, looks really nice! Average viewing distance is a big factor as well.
Most digital visual effects for 35mm and features finished to anamorphic 35 are rendered at 2k resolution. A few years ago I did most of the animation on a 35mm film spot for American Express. It was rendered at 2k and transferred to 35 and it looked gorgeous. If you have very sharp spatial resolution in your 2k image (such as computer generated imagery where every pixel is sharp and perfect) you will not gain much of an advantage going to 3k or above. The only thing that kind of resolution is useful for right now is IMAX. I dispute the idea that 35mm has 4k of useful pixels. After about 3k you won't percieve any practical difference.
CCD technology will not be able to replace film (35mm) for at least another 5 years, if ever.
5 years for widespread distribution is practical. "ever" is ridiculous. :)
Remember, when talking technology, think about practical application and end results. pixels don't exist in a vacuum. (but when they're on a CRT they exist in a vacuum tube! :)
Personally, I'd like to see variable frame-rate 2k to 3k systems for regular movies, and 4k - 5k digital systems for IMAX sized projections, using a format that can be created and previewed on desktop PCs with very fast disk arrays and hires monitors. (check out IRIDAS for an excellent digital cinema and desktop hires playback system, including 3D!)