35mm = 4K (in dlp chips)

Peter, 35mm as a display medium, rather than a capture format, is nowhere near the performance of 4k. Its ability to display detail is actually significantly lower than 1080p/2k systems. This confusion of capture and display performance of film has led to a huge amount of misunderstanding in this area. Kodak Vision 200T color negative 5274, as an example, can capture 4000 lines, but that is not representative of a release print with its cascading generational MTF reductions. Thats even before it meets the PJ, let alone the image that actually falls onto the screen.

I can display a pristine print back to back with its BD equivalent and very easily see the superior small area contrast and detail, ie resolution and MTF, of the digital system. Thats with a 35mm image well beyond a normal commercial cinema.

If you wish further detail, just holler.

I have just read your OP again, and now see that I actually misunderstood it originally.

For anyone else who read my initial reply to Peter, it may look like I was dissing film. Nothing could be further from the truth.

Yes, great informative post. Coldmachine, the subject gets particularly interesting when film grain is added to the mix. Most people consider film grain to be the analog equivalent of pixels -- simply the medium artifact which is the limit for resolution.

But I love film grain, and think it can be an intrinsic part of the film viewing experience -- kind of like artist brush strokes. So here, digital actually doesn't have the resolution yet to reproduce 35mm film grain!

Of course, atavist that I am, I also love B&W!

Regards,
Terry

What is the inherint significantage advantage of 2K over consumer 1080p? 2k is 2048 x 1080 while consumer is 1920 x 1080? Is that 128 increase in resolution in one direction or approximately 140,000 additional pixels significant?

I'll try to stick exactly to your question, as this has the potential for Peter and I to get into one of our cage matches.

The resolution difference is so small as to be able to be regarded as almost non existent. There is effectively no difference in resolution.

Where there is a significant difference is the actual chips used. The larger 2k chip is 1.2" as opposed to the smaller 0.95" used for domestic units. The bigger chip has a better fill and has a better pixel noise performance. If all other factors are identical (which they never are) a 1.2" chip is capable of rendering a higher fidelity image and allows for closer seating. There are also .98" 2k DMDs.

Genuine 2k content is another factor, as a DCP (Digital Cinema Package ie the DCI movie) is a very significant step up from domestic 1080p content. Better colour, less compression and much higher data rate.

Wow, some-one mentioned hyperbole, you just downgraded your little beamers to one third their proclaimed glory, from 70mm to 25mm.

Coldmachine the .98 chip is also 2K, the .95 or .65 chips aren't, those are 1920.

Thanks, I was getting my DMDs confused.

I meant .95" rather than .98" in my post above. Its been amended.

Thanks CM. I do know the differences between DCI source material and what we have at home and the reproduction chain from the source to the screen. The biggest differences I assume would be the data rates which the DCI standards sets as a max rather than a minimum and having 12 bit video rather than the paltry 8 bits we have at the consumer level standard which regardless of the rest of the chain without the DCI source is unobtainable in our home. Basically although we can purchase fully DCI compliant machines for our homes, we get some improvement because of the better chips as you point out, but?

In reading the standard I note the digital camera standard is a 2.6 gamma. Now I KNOW of no projector other than a CRT projector that has a high enough on off CR to allow the use of a 2.6 gamma at projector. Black crush. At home or in the DCI cinema. So obviously they don`t project using a 2.6 gamma or do they?

Peter employs an s-shaped gamma curve on his tanks. Search the forum for depthfx/depth-fx, the knee points are top secret though;-).

DCI content is encoded with a pure 1/2.6, then decoded with a pure 2.6 during playback. In other words, the decoding is the exact inverse of the encoding. So if there is any black crush, the black crush probably already existed before it was encoded for DCI in the first place.

This is different from regular video, where the camera encodes with the Rec709 OETF, which has a linear tail, and then the display decodes with a pure 2.35 or thereabouts. The decoding is higher than the inverse of the encoding, so black crush might appear.

Just wondering: If 4K should come to home cinema sooner or later, which size do you expect the 4K DLP chips to be? 1.375"? Or do you think they'll shrink the chips for home cinema?

With a chip this big won't the anamorphic lenses run into trouble? I mean the light beam will be quite big then, too, won't it?

Hmmm... What solution do you think will be used for CIH setups then? Zoom memory? Or simple scaling?

most talk about 4k in home is premature by about 20 years at least. the simple fact is there there is too much infrastructure invested in 2k HD for a switchover to happen. there is a tremendous amount of ROI to be realized first.

Having said that, the simple fact is there is also SO much room to improve both the source and playback devices in the 2k world that in reality, we are at a point in the 2k realm that is similar to about 1978 in the standard Def world. on the most part, we have not yet begun to see the best that we can get in 2k. not even close really.

4k projectors may make some improvements in how a 2k image is viewed, however i would rather have a more mature (BETTER) 2k machine than a newer 4k machine if that makes sense.

True. But the question is if 4k chips will have any disadvantages compared to 2k chips. If not, they might still be worth it, cause they'll definitely have a couple of advantages, even with 2k content. The next question is if projector manufacturers would have much extra work with implementing 4k chips. If yes, that might delay important other improvements. If no, the only disadvantage of going 4k would be higher cost.

a 4k chip can also introduce optics. to make it happy, you need a whole different class of electronics, and also lenses that are at a whole different level in order to realize all that extra resolution. and that in and of itself can be VERY pricey.

A 4 k proj with optics on par with a 2k machine can look worse than a 2 k machine with 2 k optics. remember that lenses have resolution, and depth of field and all sorts of other elements that contribute to image quality. i am simplifying a bit, but make sure that you do not forget that all elements of the system contribute to overall image resolution.

so i am just saying that we have a long way to go in thye 2k world before we can make categorical statements about 4k being some sort of saviour.

proper terminology for a non zoom lens is a prime lens. ALWAYS preferable to a zoom lens. if it is an option

Thanks for the replies, guys, appreciated.

Good article. Here is a good out take from the article.

Let's just pretend for a moment that IMAX truly is 4K. You watch IMAX at between one and one and a half picture heights from the screen. But in order to get to appreciate 4K on a regular movie screen, you would have to sit much closer than normal. In other words, when you go to a movie theater, and most of the modern theaters with stadium seating are designed so that the middle of the theater is 2 ½ to 3 picture heights from the screen, for most of us who watch movies, that’s pretty where we want to be sitting. Maybe just a little bit closer from some of us who do this for a living, because we're maybe looking for artifacts or issues. If you sit much closer than 2 ½ picture heights, that's what you're seeing, artifacts, not movies!

So if you had true 4K resolution in your local theater, everybody would have to sitting in the first 6 rows. Otherwise they wouldn't see any extra detail. Their eyes wouldn't LET them see it. You know this intuitively from passing by these beautiful new monitors at trade shows. You find yourself getting absolutely as close as possible to see the detail, and to see if there are any visible artifacts. At normal viewing distances, you can't.

So the whole 2K 4K thing is a little bit of a red herring.

.........that would be 2.5 to 3 heights is with 2K DCI material or film, but I'm sure a 4K chain would benefit the guys who sit @ less than 2 screen heights with BluRay!!

What about all the compression artifacts in BD. Are you guys saying you do not see them or are you saying a 4K display will mask them?

I would never want to see BD on a ultra bright machine sitting closer Id cringe. Keep in mind I am not talking about the few titles that look good or animation these are not the norm I am talking about the other 80 to 85% of BDs library.

By the way if you visit some of the film forums where theater techs hang out who install DC equipment in theaters they complain about the artifacts in some of the DC content. BD is obviously worse due to the compression scheme used.

Agree 100%......I too see them on BD any closer than around 3x screen heights on an average encode.

I was saying 4K source material on a 4K machine, would be of benefit for those who like to sit at closer ratios. Some sit at less than 2x screen heights with BD and I wonder how they don't see the distracting compression artifacts. IMO BD does not have the detail to support viewing at those close distances.