Film-Tech Forum ARCHIVE: Giant screen aspect ratios in the future

This is topic Giant screen aspect ratios in the future in forum Large Format Forum at Film-Tech Forum ARCHIVE.

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Posted by Antti Nayha (Member # 4980) on 01-11-2012, 12:49 AM:

With the transition to digital, is the giant screen industry moving towards a widescreen aspect ratio? Are new venues, designed for digital from the ground up, still being built with a 1.33–1.44:1 screen? I’m not talking about multiplex LieMAXes showing Hollywood blockbusters in 2K, but traditional giant screens showing dedicated giant screen content in 4K.

There was some discussion at LF Examiner after last year’s Digital Symposium, but no comments really about future practices.

Simply zooming a 1.9:1 native D-Cinema projector to fill a 1.33–1.44:1 giant screen doesn’t seem like a good idea, when digital is already struggling with light levels on these screens. An anamorphic squeeze of 0.7x(ish) would seem like a good idea, but is anyone doing it?

Perhaps the next Digital Symposium (held in two weeks time) will shed some light on this.

Posted by Dick Vaughan (Member # 540) on 01-11-2012, 04:17 AM:

The "next" digital symposium finished yesterday. Unfortunately I wasn't able to attend so waiting to get updates from my colleagues.

Posted by Antti Nayha (Member # 4980) on 01-11-2012, 04:46 AM:

Ah, OK, so I was a bit mislead it seems. Will be interesting to hear the news.

Posted by Dick Vaughan (Member # 540) on 01-11-2012, 04:59 AM:

Yes that was last years's symposium. [Roll Eyes]

there are proposed standards for Giant Screen Digital which you can read about on the Giant Screen Cinema Association website .

News article here

Posted by Antti Nayha (Member # 4980) on 01-11-2012, 05:36 AM:

Thanks for the heads-up – both with the DIGSS standard and the year! [Big Grin]

Posted by Bobby Henderson (Member # 840) on 01-11-2012, 08:44 AM:

I'm surprised there's there's any sort of "digital" development going on with large format theaters other than just trying to survive by taking a giant step downward quality wise with digital.

15-perf 70mm film is great on a giant sized screen. Digital sucks on a giant sized screen. Even 4K really isn't good enough for an IMAX sized screen. It may be acceptable for a standard movie theater screen geared for 4/35mm projection since 4K is close to what 35mm can deliver. The fixed 4K pixel grid will be small enough on a standard sized movie theater screen to hide jaggies and other signs of native resolution limits. 4K isn't a worthy replacement for giant screen 70mm.

When digital projectors can get into the 8K range (with native photographed/rendered content) then it might raise my interest in giant screen digital.

Posted by David Zylstra (Member # 4230) on 01-11-2012, 03:43 PM:

I was at the symposium . . . . the theatre we were in had been converted to dual 4K digital projectors. For the side by side demo of digital vs. 15/70 they claimed 14FL at 90% power on the digital with the picture within 3-4' of the 4:3 screen height (I forget what they said the screen size was). Surprisingly the 4K image looked good next to 70mm.

I was not able to watch the "real" content they showed so I do not know how much of the screen they normally fill.

Posted by Victor Liorentas (Member # 5272) on 01-11-2012, 05:21 PM:

It's kinda important to know the size and what content was being shown on this screen.No chance dual 4k looks better than 15/70 unless they stack the many variables in favor of the 4k.

If it was a silver screen it will also take away from the pure awesome look of 15/70 at it's best.The 4k projectors have integrating rods to spread the the light more evenly,one of the great strengths of digital projectors.

Posted by Alan Gouger (Member # 543) on 01-11-2012, 06:39 PM:

This years event:

http://www.systemscontractor.com/article/69260.aspx

Posted by Aaron Garman (Member # 1653) on 01-11-2012, 07:29 PM:

I find it funny that they are pushing 11.1 but all the speakers in the world won't get you good sound with out good EQ skills. I'm sure Bobby will agree.

AJG

Posted by Bobby Henderson (Member # 840) on 01-11-2012, 08:57 PM:

On audio the EQ skills are vital. It makes a tremendous difference between yielding great sound quality and mediocre sound quality. It also goes without saying the room acoustics and sound system design must be very good in order to provide a solid foundation for those EQ skills to be fully effective. When you have all that come together and you feed the audio system a good movie mix the result is pretty amazing.

Regarding "11.1" or whatever audio format someone is promoting, all the extra amplifiers and speakers won't do much additional good unless the movie mix is made in that format. This reminds me of all those "7.1" receivers from years ago, even before DD-EX & DTS-ES, that were really nothing more than 5.1 receivers summing the stereo surrounds to more speaker outputs. I remember seeing one Yamaha receiver that was something like 11.2 channels. That might be good if the receiver was handling two different 5.1 audio streams and feeding them into two different rooms. Otherwise it's a freaking waste because no movie mixes are made in any more than 7.1 channels. The vast majority are only 5.1.

Posted by Antti Nayha (Member # 4980) on 01-17-2012, 07:53 AM:

Bobby, I’m pretty sure that most of us here (including myself) are very sceptical about 4K holding up on a giant screen. People who have actually seen a demo, however, seem to be saying that it looks surprisingly good next to 15/70mm… check out the LF Examiner link in my first post if you didn’t already.

Anyway, the DGISS proposal already says that 8K should be ”recommended” for giant screens in the future. They also support the 1.33:1 ratio.

But I think your comment about survival was spot on. For example, how long will 8/70mm prints of educational giant screen films be available? It’s not like 8/70mm venues are going to change to 15/70mm now, so 4K digital is the best they can currently get…

Posted by Scott Norwood (Member # 30) on 01-17-2012, 08:38 AM:

Here's my crazy idea: take three standard DLP projectors (1080x2048) with anamorphic lenses, orient the 2.35:1 images vertically, and tile them left to right. That gives you an almost 1.3:1 ratio and 3x the resolution of 2k DLP. It also has a nifty Cinerama-like quality....

Posted by Brad Miller (Member # 2) on 01-19-2012, 01:20 PM:

quote: Antti Nayha
They also support the 1.33:1 ratio.

Wow. People, let it go!!! Height does nothing without width. It is like watching someone's camera phone video where they are too stupid to turn the phone sideways.

Humans have 2 eyes located BESIDE each other. We aren't one-eyed. If we were, then 1:33 would probably be fine, but screen width is needed.

Posted by Jack Theakston (Member # 4484) on 01-19-2012, 02:08 PM:

The problem is that field of view is not so clear cut. Peripheral vision CAN lie on average in the 4:3 range, and your center of gaze falls somewhere in the 2:1 aspect ratio area. But when ever have you seen an immersive 4:3 set-up?

Posted by Frank Angel (Member # 248) on 01-23-2012, 10:38 PM:

With any 15/70 IMAX presentation, yes, there is an impressive feeling of being enveloped and immersed in the image, BUT that is because of the extreme 80ft width of the IMAX image, it's not because it's 4:3 ar. The immersive feeling is derived from filling the peripheral vision, and to do that you need basically a 2:1 screen big enough. Can anyone say CINERAMA -- one of the best immersive process to date and they did it with a 3:1ish ar.

In all original IMAX films, there was care to insure that primary action stayed pretty much within the natural human 2:1 field of vision. Sure there was height, but objects of importance were composed centrally so a viewer was rarely confronted with the issue of having to choose between important object placed at desperate positions top and bottom of the screen.

Those films were shot and composed SPECIFICALLY for the IMAX screen. Hollywood films are not. Unless one can envision a scenario where Hollywood will compose two different versions of a release, one for scope and one for the original IMAX academy-ish ratio, IMAX is doing the only thing it can do now that they realized that doing IMAX documentaries would put all their upper management in the poor house -- they are converting all their theatres to standard scope ratio screens, albeit somewhat bigger than average, but nothing to right home about. Now they have to figure out how in hell to make a SCOPE ratio screen bigger than conventional screens and still make it look good....and trying to do it with 2K digital, no less. Good luck with that dog poo.

Posted by Scott Jentsch (Member # 1681) on 01-28-2012, 07:29 PM:

quote: Bobby Henderson
This reminds me of all those "7.1" receivers from years ago, even before DD-EX & DTS-ES, that were really nothing more than 5.1 receivers summing the stereo surrounds to more speaker outputs. I remember seeing one Yamaha receiver that was something like 11.2 channels. That might be good if the receiver was handling two different 5.1 audio streams and feeding them into two different rooms. Otherwise it's a freaking waste because no movie mixes are made in any more than 7.1 channels. The vast majority are only 5.1.

Bobby,

You might be thinking of the Yamaha RX-Z11, which was introduced in 2007 and had 11.1 channels. Pre-lossless audio, the RX-Z1 was 7.1 channels and released in 2002.

Even though those receivers had more channels of output than the source material could provide, Yamaha has always been known for its signal processing, and those extra channels were used by the DSP's to create a larger soundfield. Whether the DSP effects were effective or not was a subjective opinion. The current top-of-the-line Yamaha RX-A3010 is a 9.2 channel receiver, so they've backed off on the number of distinct channels they're offering. (The extra two channels are front-height channels)

Simply repeating the outputs would be lame, I agree. However, doing some optional processing to achieve additional effects is fine in my book. If the extra channels give the marketing guys warm feelings, everyone wins.

As far as theater sound goes, if extra channels help to fill in any holes that there might be in the soundfield, that's great. If those extra speakers can then be used for additional distinct channels if the studios ever use them, what's the harm?

Back to the topic at hand, the DIGSS 1.0 spec lists the following aspect ratios:

4096 x 1716 2.39
3996 x 2160 1.85
4096 x 3072 1.33
2048 858 2.39
1998 1080 1.85
2048 x 1536 1.33

So that tells me that they're still looking to support 1.33:1. I think it makes sense to have a 1.33:1 screen, as it provides the most flexibility, and unlike traditional theatrical screens, the top and bottom masking that would be necessary would not be impacting the size of the content. 1:33:1 IMAX and giant-screen movies were intended to be shown on such "over-tall" screens for the reasons mentioned in earlier posts (2:1 protection area, with the extra vertical area for impact).

Posted by Marcel Birgelen (Member # 6801) on 03-06-2012, 02:04 AM:

quote: Scott Norwood
Here's my crazy idea: take three standard DLP projectors (1080x2048) with anamorphic lenses, orient the 2.35:1 images vertically, and tile them left to right. That gives you an almost 1.3:1 ratio and 3x the resolution of 2k DLP. It also has a nifty Cinerama-like quality....

I've never seen 3-strip Cinerama with my own eyes, so I'm wondering how noticeable the seams between the edges were.

I've seen multiple-projector setups in a few digital dome-based platetarium configurations and they seem to do a pretty decent job at edge blending the images together. Yet, the images projected here were all in the low ends regarding brigtness and contrast.

Has anybody ever seen a working multiple projector solution on a huge screen with e.g. 3 or 4 projectors that offers near-perfect edge blending between the separate images?

Posted by Cameron Glendinning (Member # 3516) on 03-28-2012, 08:42 PM:

Any opinions regarding the 4k, 48 frame per sec demo's?

Posted by Brad Miller (Member # 2) on 03-28-2012, 10:31 PM:

quote: Jack Theakston
The problem is that field of view is not so clear cut. Peripheral vision CAN lie on average in the 4:3 range, and your center of gaze falls somewhere in the 2:1 aspect ratio area.

I certainly see "wider" than 2:1. If I just look straight ahead I can see what must be close to 180 degrees of width, but not all that much height. Maybe its not the norm, but I can't watch a 1.85 movie and forget I'm watching a movie.

quote: Cameron Glendinning
Any opinions regarding the 4k, 48 frame per sec demo's?

Yup, the 48fps ruins it.

Posted by Marcel Birgelen (Member # 6801) on 03-29-2012, 08:02 AM:

quote: Brad Miller
Yup, the 48fps ruins it.

What exactly ruined it?

Posted by Brad Miller (Member # 2) on 03-29-2012, 10:39 AM:

There are other discussions on this. It makes the image look like 1980s video. Sure the resolution is there and it is sharp with great optics on the cameras, etc...but the motion makes me feel like I am watching cheap 1980's sitcoms on tv.

Posted by Bajsic Bojan (Member # 4928) on 03-29-2012, 04:00 PM:

quote: Scott Jentsch
Back to the topic at hand, the DIGSS 1.0 spec lists the following aspect ratios:

4096 x 1716 2.39
3996 x 2160 1.85
4096 x 3072 1.33
2048 858 2.39
1998 1080 1.85
2048 x 1536 1.33

i spent quite a while reading this digss document and cannot gather how they mean to project the 1.33 image. They apparently acknowledge the fact that the container is smaller, then they put an absurd number which basically makes no sense in there.

Posted by Marcel Birgelen (Member # 6801) on 04-04-2012, 03:53 PM:

quote: Brad Miller
There are other discussions on this. It makes the image look like 1980s video. Sure the resolution is there and it is sharp with great optics on the cameras, etc...but the motion makes me feel like I am watching cheap 1980's sitcoms on tv.

Sorry, I didn't really follow any recent discussions about this.

I guess most sitcoms were shot on video at 60 or 50 fields/second rather than 35mm, because of budget constrains. There always was a lot of light in the studio resulting in fairly high shutter rates. So there was not very much motion blur in those images.

Filming in 48fps or more is still quite rare, so cinematographers still have a lot to figure out. Also, I guess after all those years watching movies at 24 fps our mind might have been subconsciously trained on how a motion picture should look like.

Still, I think a higher frame rate will give cinematographers a powerful tool, that, if applied correctly, can also greatly enhance our movie experience.

Posted by Antti Nayha (Member # 4980) on 04-05-2012, 08:08 AM:

quote: Marcel Birgelen
I guess most sitcoms were shot on video at 60 or 50 fields/second rather than 35mm, because of budget constrains. There always was a lot of light in the studio resulting in fairly high shutter rates. So there was not very much motion blur in those images.

Not quite right… The ”sitcom look” has traditionally used ”360° shutter angle”: 1/50 sec when shooting 50i, or 1/60 sec when shooting 60i. That means the amount of motion blur in a single frame is actually close to that of typical 24fps film (1/48 sec). The reasons why the video motion looks very different is 1) the higher framerate, and 2) the fact that all the motion is there – there’s no stutter, since nothing is missing between frames!

”The Hobbit”, on the other hand, is being shot at 48p with a 270° shutter angle, which amounts to a shutter time of 1/64 sec. This still gives you a very slight ”filmlike” stutter compared to the traditional sitcom stuff. But I guess we’re hijacking the thread…

…so getting back on track: I was also wondering about the 4:3 resolutions in the DIGSS proposal. It’s not like TI is going to produce a special DLP chip design for a handful of giant-screen cinemas. A more realistic solution would be to use an anamorphic lens to stretch the 4096x2160 image vertically – either that, or tile up multiple projectors.

Posted by Antti Nayha (Member # 4980) on 01-22-2013, 04:59 AM:

Resurrecting another old thread… (I don’t know if this should be moved to the digital forum though - the whole thread was always about ”the future” and the future is digital as we know.)

It seems that we already have a working implementation of the DIGSS specification, complete with a 4K × 3K resolution: Global Immersion’s GSX™ giant screen projection system was installed last autumn in the Peoria Riverfront museum in Illinois. I'm attaching the full press release below; some musings follow after that.

quote:
Global Immersion GSX Digital Giant Screen Cinema to Premiere at Peoria Riverfront Museum

September 26, 2012
Global Immersion, a leader in the field of high performance immersive theater, has confirmed the première of the world’s highest performance and most versatile digital Giant Screen Cinema system, GSX™. On October 20, 2012, the new Peoria Riverfront Museum (PRM), Illinois, USA, will open to the public with the first GSX giant flat screen theater. The facility will become the highest resolution digital Giant Screen Cinema in the world capable of 2D and 3D presentations and will be the only theater to offer multiple, automated aspect ratio modes including 4:3 at 4K by 3K resolution.

Since being approved in 2001, the PRM project in Peoria, Illinois, has worked to clearly defined objectives to become a cultural center for art, history, science and achievement through the application of pioneering design, technology and innovation.

Following contract award in 2010, Global Immersion has collaborated with PRM and its team of technology and consultancy partners to develop the state-of-the-art theater which will launch next month. The new theater system is now available as part of Global Immersion’s GSX series of digital Giant Screen Cinema systems, each designed for the emerging Digital Immersive Giant Screen Specification (DIGSS), promising unrivaled performance and unrestricted content capability.

Product of an ambitious and visionary approach.
The PRM theater, powered by GSX, will feature a 70 x 52 feet / 21.3 x 15.8 meter screen, 200 seats, and a range of features unique to GSX that will enable the museum to play an unrestricted range of content including traditional giant screen films, streamed, alternative, live and online media in multiple aspect ratios and file formats (including Digital Cinema Initiative [DCI]-encrypted films). The system is capable of playing content at up to 60 frames per second and in 12-bit color depth.

Speaking about the project, and the unique capabilities of the new system, Martin Howe, CEO at Global Immersion commented, ‘We are incredibly proud to be delivering the first GSX to such a visionary team of museum and technology professionals. Since the beginning, we have worked diligently to evaluate the best possible technology choices and partners, and to set ambitious goals for our digital Giant Screen Cinema system in order to provide a high performance platform that rivals and even outperforms the quality of film and yet offers the broadest possible range of content for the Giant Screen Cinema world.”

Jim Richerson, President and CEO of Peoria Riverfront Museum says, from the beginning the Museum has been focused on creativity and innovation. “Clearly Global Immersion's GSX system delivers that and more. With this system Global Immersion delivers several industry firsts and this will most certainly ‘Play in Peoria’! Key to serving our mission and bottom-line is a system like GSX that is flexible in programming and technologically upgradeable.”

Exceptional brightness and versatility with exclusive features.
Global Immersion formally announced the GSX™ digital Giant Screen cinema product line in March this year. The GSX range of theater systems comprises GSX for flat or curved Giant Screen theaters, GSX Dome™ for in-dome Giant Screen insert display systems, and GSX Fulldome™ for digital Giant Screen fulldome theaters. Each of the GSX systems is available in both 2D and 3D configurations and is designed to exceed the performance of traditional Giant Screen film projection.

The GSX theater system at the Peoria Riverfront Museum will deliver up to 6 foot-lamberts (ftL.) of brightness in Giant Screen 3D mode in 4:3 aspect ratio; a 3D image at least twice as bright when compared to alternative Giant Screen Cinema systems.

Fully DCI-compliant and designed for DIGSS, GSX uses a dual projector design to achieve True 4:3™; a feature which projects 4,000 by 3,000 pixels in 4:3 aspect ratio to deliver 12 million unique pixels on screen. The product is the only digital Giant Screen Cinema system in the market today to project 4K by 3K resolution, and does not use ‘over-projection’ or ‘masking’ techniques to achieve 4:3.

The system is the only digital Giant Screen Cinema solution available offering automated multiple aspect ratios at the push of a button, including True 4:3™; enabling theaters to rapidly switch between 16:9, 1.85:1, 1,89:1, 2.39:1, and True 4:3™ modes on demand without loss of resolution or brightness.

“We have created an industry-leading solution which addresses the demand for ultra-bright Giant Screen 3D, and will expand the content library available to Giant Screen theaters,” concludes Howe. “Not only does GSX set new standards for digital Giant Screen Cinema, but it goes beyond the expected and allows theaters to choose, see and experience more than ever before.”

So it looks like they went with a dual format system to support both DCI and DIGSS content. According to my information, they have two 4K DCI projectors fed by both a Qube DCI server and Global Immersion’s DIGSS server. The latter can run a variety of content, including 4K × 3K.

They proudly claim that they don’t use ”’over-projection’ or ‘masking’ techniques to achieve 4:3”. I wonder what that means exactly – are they just tiling two 4K images on top of each other? Technically that would still be over-projection or masking, since you’re only using 1536 vertical pixels from both projectors instead of the full 2160. Unless they’re using anamorphic lenses on both projectors, but that would make an awfully complicated optical system since they’re also using RealD XL (or something similar).

Anyone more familiar with this one?

Posted by Lyle Romer (Member # 1266) on 01-24-2013, 06:26 AM:

As others have said, the reason IMAX is immersive is that the screen is wide and you are sitting close to it. The height is kind of a byproduct. It's nice that when you look up you see the sky instead of the top edge of the screen but I think it's more an issue of sheer size than aspect ratio.

I assume the IMAX aspect ratio was created by default. I'm guessing they wanted a bigger frame with more light than 5/70mm. If they just made the frame taller it would have been a ridiculously narrow AR so they turned the film sideways. They decided the width of the frame should be 15 perf probably for light and mechanical reasons and then figured they'd use all the available height of the frame which led to the AR.

Posted by Steve Guttag (Member # 268) on 01-24-2013, 08:39 AM:

That is a nice theory...but it doesn't hold water. The extreme height has always been a hallmark of the IMAX image...if one goes back to IMAX's roots as a World's Fair thing and then museums like the Smithsonian or the Cinesphere. The signature movie of the Air and Space museum in DC was/is "To Fly" which depicts, among other things, rocket ships shooting off...something that would be diminished if the height of the screen (relative to width) were lessened.

While I don't dispute that the ratio came about due to physical properties of 70mm film and the machines they going to use to film/project it...the movies that were to be shown in the format went hand-in-hand with it (each were designed for the other).

Posted by Scott Norwood (Member # 30) on 01-24-2013, 09:02 AM:

Also, a true Imax film is composed differently from a 1.37:1 35mm frame. Rule-of-thirds does not apply. With Imax, the central subject is typically positioned in the lower center of the picture, with the rest of the frame being peripheral. This is most clearly evident on dome screens, but can also be seen on flat screens.

Posted by Jonathan Goeldner (Member # 4854) on 02-16-2013, 03:46 PM:

what's the audio specs of Global Immersion’s GSX series theaters - standard 5.1 (or 7.1)? How many speakers can be implemented?