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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.
here
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.
Compression Rates are completely different that FRAME SIZE. DVD has a frame size of 720x480. Although The dvd spec allows for a couple others 1/2 D1, Mpeg 1 (Compression Type change), All major studio DVD are at the SAME FRAME SIZE 720x480. You may be referring to the variable bit rate encoding MPEG II.
Meatplow.
Try this.
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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.)
I had the same experience. I saw AOTC DLP and was not impressed. I saw it again later at 2nd-run theater and the non-digital projection actually seemed better.
I went to see Nemo the first weekend it came out. I happened to get a DLP showing (didn't hunt for it like I did with AOTC) and it was really good (far better than star wars). I saw Nemo again the next weekend with another group, this time regular projection. I have to say the digital projection was sharper and had better color.
Now I want to go see it a 3rd time, back to DLP to see if it really was that much better, or if I'm imagining it.
There is much cruelty in the universe, John.
Yeah, we seem to have the tour map.
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...
You don't just get up and change something like that. The reason film is 24 fps is because that was the best flash rate people could stomach financially back in the day. 48 fps provides enough light on the screen, but since not very much more than 24 is needed for fluid motion to our eyes they film it at 24 and flash each frame twice in the projector. Do you notice that more and more TV shows (24, angel) are being filmed at 24 frames per second instead of normal American TV's 29.97? It is much more pleasing to the eye.
I am not trying to be too harsh but the trend is moving TOWARDS 24fps instad of or 120Hz or whatever you're thinking would be better. HDTVs do flat out 1920p 24fps now. that's getting closer to film quality than older TV. 35mm film is approximately 3.1 megapixels in theory (2048x1536, box your frame afterards and it's a bit lower), but its color range is millions and millions of colors, which no camera, not even G. Lucas' little pet project can pull off as of yet. Film is a very rich medium that will not be removed from its position for a while yet IMHO.
Wow, ok </rant>. Sorry. Ever heard of Nyquist? He basically figured out that if you want to accurately capture data (in this case it would be our eyes capturing images) you must sample at twice the rate of the original source. It works slightly backwards in this case. If we are to see perfectly fluid motion we would have to feed 60 images per second to our eyes, because since average eyes see ~30fps that is twice the rate. Think about when you point a camcorder at a monitor. You get those weird dark bands that slowly creep up or down he screen. What you are actually seeing is the camcorder's framerate conflicting with the monitor's frame (refresh) rate. Tilt the the camera along its Z axis about 50 degrees, and poof, no more bands. Alternatively, jack the refresh rate of your monitor up to 120Hz and the Nyquist theorem states that you will cease to pick up dark bands on the camcorder. Put it at 30Hz (not an option for many I know) and you will see ONLY "dark bands."
My apologies again since that was not really relevant to your "gripe" but alas, it's been typed. My main point is that we've been given "quality" that matches our physiology. People for the most part have settled on current framerates because they look good to most. People are gaining acceptance for wide format movies which IMHO are much more pleasing to the eye than 4:3 TV shape. I am definitely NOT saying that you are stupid or distasteful, but I am saying I like things where they are. Nothing needs to be faster than 60Hz/fps because we can't see any quicker than that. IMO 24fps looks better anyway. Many movies (Saving Pvt Ryan, Fast and the Furious, American Beauty, Braveheart, Fight Club just to name a few diverse titles) have decided to accomplish slow motion by filming a shot at the normal framerate and using a technique called frame blending, where the frame rate is cut in half and instead of showing every frame twice (1,1,2,2,3,3,4,4) it cross fades every second frame (1,1/2,2,2/3,3,3/4,4). It makes for a very interesting and suave alternative to burning up more film on slo-mo (a la 800fps in Snatch, but damn that was cool).
The uncompressed data stream off a Sony Cinealta (HDW-F900) digital HD camera (the same that Lucas used in AOC), is 1.5Gb/sec. I believe it's essentially a Fibre Channel connection. Uncompressed, you can store 3.5 hours of 1080i 24P footage on a 720GB array. You want bigger and faster? Now it really starts getting expensive.
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There are some serious technical hurdles with bumping up the frame rate and resolution on a digital camera (can you imagine handling a 12Gb/sec data stream?), but surprisingly, I think we'll start seeing some of those hurdles being overcome in the next couple of years.
Now, when it comes to price. .
You can rent a Cinealta for about $1500 a day. The price goes down for multi-day shoots. That's 30 minutes of raw 35mm film and that doesn't include processing. If you run 35mm at 48P, then that cost doubles. On average, the filmmaking group I am a member of, tends to record between 1 and 2.5 hours of footage per full day, depending on the number of cameras used, the number of takes, etc. It's a no brainer to jump to HD instead of 35mm.
But the real bottleneck is the projection. Just because you could theoretically record in 35mm 48P, or QuadHD 60P does not mean that you can project it as such. The goal of digital filmmaking isn't merely to increase the quality, but to reduce the costs in every aspect of a production: filming, editing, and distribution.
We've got a ways to go, but we will get there.
Moekandu
Mediocrity knows nothing higher than itself; but talent instantly recognizes genius. -- Sir Arthur Conan Doyle
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!)