IMAX Technology Chief on 'Dunkirk', Christopher Nolan and Future Advancements

Culture Trip (CT): What lies behind the success of IMAX in recent years, and which filmmakers do you think are making best use of the technology?

Brian Bonnick (BB): There’s a secret sauce [to producing films specifically for large screen formats]. We often work from cradle to grave, but there is no one particular thing we do to keep things immersive. It is a combination of a number of things starting right at the beginning, with the camera technology for the filmmakers themselves…

They make the image grow vertically, which is a creative decision. They take advantage of the soundtrack and remix it in IMAX to add bass.

Christopher Nolan is a big fan of that. He used it on The Dark Knight and will be using it in the upcoming [World War II drama] Dunkirk. He’s actually filmed quite a bit of it using these super high-resolution cameras.

The Dark Knight is one of my highlights, but Nolan’s new one, from what I’ve seen, will be hard to beat. The cinematography, the realism, all based on the trailers in the venue. I almost felt like I was getting stressed!

In Dunkirk, there is a dogfight sequence between planes and you feel like you are sitting in this plane. It’s the most realistic thing I’ve ever felt. The whole theatre was vibrating and you feel like you are in this vintage aircraft. I was amazed by that. All those directors get it. The camera, the audio and they also take advantage of the massive field of view. They know how to integrate technology with the creative part of it.

Michael Bay makes great use of the screen and so does JJ Abrams. Most of these are a select group of premier filmmakers and they are that because they tend to be more creative in a technical sense. It’s amazing how well they understand the technology behind projection and audio. They take advantage of what we can give them. They increase the aspect ratio.

I’m a film nut. I love watching films in this format. I like the sound better than the visuals. You could watch a silent movie in the old days and you could see it all, but you would never really get the tone. Sound brings that out, and that lower octave really blows the doors of any cinematic experience.

CT: What are the other elements of the process?

BB: We then have our post-production where we digitally remaster both the audio and the visual. That’s the process of DMR [digital media remastering]. Most enhancement technologies look at a frame and try to clean it up and remove noise. When they do that, they invariably lose sharpness. What we do is to approach it temporally. Think of it as a speck on my nose. If you see that in a single frame you don’t know if that is dirt or a mark on me. Now if you do it over multiple frames you can follow my nose as it moves across the screen. It gets quite complicated. We are able to determine what is real content and what are artefacts of noise. We can clean it up without losing sharpness.

We do the same thing on audio. We go an entire octave lower. If you imagine going to a concert, you know how your body palpitates and you “feel” the sound? It’s that feeling you get with lower octaves. The room is acoustically treated and the speakers are always custom-designed by IMAX to fit the room.

All of the equipment feeding the loud speakers is also custom, not because we need to play it loud, but because want to maintain those big moments without any distortion coming through. We design the theatre for specific reverberation characteristics. The idea is that every IMAX theatre should sound like the next one. We also use a system called PPS (Proportional Point Source) and what that does is distribute more sound energy to seats farther away from the screen than those close to it. The energy dissipates but we have a wide sweet spot. You down’t have to sit dead-centre.

Finally we have the projectors. We have a laser-based system, and the historical problem with that is that digital projectors suffer from brightness, poor contrast and poor image sharpness relative to film-based projectors. That’s been there since day one. It’s because there is a prism to move the light around and then it gets redirected through a sensor. The problem is stray light, which causes issues and then more glass in the system, which drastically impacts sharpness.

We threw the prism away and did a drastic redesign. We now have a $60m system using a metal frame made out of invar, which is one of the most stable materials on the planet. We can align our three chips, the red, green and blue, in a manner that gets rid of pixel drift. We then have laser technology that maintains sharpness.

CT: How do you maintain that standard the across your sites?

BB: That’s the thing we have to do for the large screen format. When we install this system anywhere you can imagine day one – that it all functions perfectly. But what happens further along the way? No one leaves an engineer on site, so we have an industrial camera that looks at the screen as if it were your eyes and we have permanently mounted microphones throughout the theatre as if they were your ears. Everyday we calibrate the system both visually and audibly, and if there is any problem in performance we get an alert. There is a facility just outside of Toronto and one in China, so it is manned 24 hours a day. We can address over 92% of any issues via the internet or over the phone, with our clients.

CT: Which is the biggest IMAX screen and how big could you go?

BB: Our biggest screen is the one in Sydney and that’s 117 ft. by 96 ft. (36m x 29m).

With the laser technology that is available, there really aren’t any limitations. If we wanted to go, say, up to a 150-foot wide screen (46-meter), we could easily do that on the technical front, but it’s very hard to find clients that have venues of that size.

The full potential of the technology really isn’t about the size of the venue or screen. As Brian explains, IMAX cinemas work just as well on the smaller format.

We have screens that are around the 50-foot mark (15-meter). We have a patent on how to convert theatres, but it’s all about immersiveness. How we achieve that is with the sound, of course, but also filling your peripheral vision. It really doesn’t matter about the size of the space we are going into.

Think about your TV which maybe 10 ft. (3m) away, and it becomes a very narrow cone from the edges of the TV to your eyeball. Now if you go closer and sit a foot from the screen, it becomes a wide cone. It’s a chicken and egg game, because as you bring the screen closer to the viewer, you are also highlighting all of the artefacts of the technology. That’s why we have all those innovations.

Whatever the size of the screen, we aim to give you that same field of view. That’s the important part. You don’t lose any of the peripheral action.

CT: Why do people still go to IMAX when we continually see home cinema evolving?

BB: Everybody loves to go to the biggest venue, when you walk into the room, it’s overwhelming. The screen and experience is nearly always the same though. People just like those big, big venues, but they are really hard to come by.

We are constantly developing the technology too. We are dabbling in virtual reality as well. I think that there are a lot of synergies between that and our core business. The viewing public are really reacting well to that. Every day we are testing new things with that.