Hidden qualities: Contrast plays a key role in our perception of 'realism'


All images aren’t born equal. Oliver Pasch, head of European digital cinema sales at Sony Digital Cinema, asks what makes a beautiful picture—and argues that genuine quality means more than counting pixels.

Why not take a look out of the window for a moment? Now close one eye. You won’t see the world with the benefit of stereoscopic vision. But even without it, there’s still a very real sense of depth to the scene in front of you. Foreground objects appear reassuringly close. The background’s definitely further away, just like it was a few seconds ago.

That sense of “near” and “far” that makes our (three-dimensional) world seem tangible doesn’t collapse the moment you shut one eye. Granted, you might struggle to save a penalty shot coming your way at 100 km/h. But nonetheless, millions of people without sight in one eye can drive, play sports and accurately judge distances without the extra benefit of stereoscopic vision.

Properly produced and projected, stereoscopic 3D is a wonderful thing to watch. But the reality is that a world presented in 2D can be convincingly “three-dimensional” in its own way. And of course, that’s exactly what directors and exhibitors have been offering to cinema audiences for over a century now.

So where does that sense of depth come from? A big part of that answer is “detail”—and lots of it. Whether they’re watching in 2D or (stereoscopic) 3D, cinema audiences respond emotionally to what’s onscreen because they’re constantly processing huge amounts of picture information. When you look out of the window, there’s an awful lot going on, however mundane the scene. Real life is detail. And as soon as you compromise on that detail, you’re immediately at a big disadvantage.

That’s why at Sony we decided right from the start that the only way to do D-Cinema was in 4K. As Christopher Nolan recently told Variety’s David Cohen, “2K digital projectors are basically just high-definition TVs projected.” From our earliest tests, we knew that audiences react positively to the clarity and realism of 4K. And as an entertainment company with some extraordinary cinematic works from the 20th and 21st centuries on our books, we were anxious to preserve as much visible detail as possible in every frame of a 35mm film.

This year, an unprecedented five Academy Award-winning movies have been distributed to movie theatres as a 4K DCP (Digital Cinema Package). In total, 4K-distributed movies earned more than 20 nominations from the Academy. And while 4K cements its presence with a rush of high-profile releases, its role is equally important in celebrating our cinematic heritage. A growing number of classic films like Lawrence of Arabia are being revisited as 4K digital restorations, letting modern audiences re-engage with our most cherished moviemaking landmarks in all their glory.

Modern display technologies are pushing pixel counts higher on TVs, smart-phones and tablets. As consumers, we’re hungry for more detail. It’s no marketing fad—it’s simply what our eyes want. Looking at a laptop or phone screen from just a few years ago can come as a big surprise: “How could anyone want to look at that?” As TV viewers, we’ve very quickly gotten used to the idea of HD as the new “standard” definition, and anything less seems unacceptably inferior. And with 4K already making inroads in the living room, depriving cinema audiences of 4K seems an increasingly short-sighted commercial strategy.

But of course pixels don’t tell the whole story. There are other factors that influence our perception of image depth and realism, and surely most significant of these is contrast. Depending on how it’s reckoned, the human eye is sensitive to a dynamic range of at least 10,000:1. While projector manufacturers play the game of “brightest equals best,” it’s onscreen contrast—the difference between light and dark—that’s ultimately more important in our perception of “realism.”

A passionate hi-fi lover doesn’t choose an amplifier solely on the basis of how loud it goes. They’re far more interested in its ability to resolve the fine dynamics of a musical passage, whether it’s a rousing orchestral climax or the delicate interplay of a string quartet. And at the cinema it’s just the same. You can shine a searchlight in your audience’s faces for two hours. They’ll certainly come away dazzled by the experience, but not in a good way. The optical engine in Sony’s SRX-R515 projector is conservatively rated with a real-world contrast ratio of 8,000:1. And, coupled with flawless 4K images, that translates into a moviegoing experience that’s wonderfully immersive, natural and believable.

Aside from spatial resolution and contrast, there’s another quite different dimension to our perception of “image quality.” Thanks to the vision of auteurs like Peter Jackson, the debate about high frame rates isn’t going to disappear anytime soon. While some critics have hailed 48fps as a creative breakthrough, others remain vehemently opposed, saying that higher rates don’t look “natural”—or even worse.

But surely the point as an industry is that we must give the creative community choice. I grew up watching films projected at a stately 24 frames per second. But that doesn’t give me the right to tell a teenager—who’s used to playing games on their PC’s maxed-out graphics card at 70fps for hours—what’s “good” or “bad.” Variable frame rates are just another tool for directors and DPs to explore, whether it’s for a whole movie or just a few action-packed seconds.

Ultimately, it’s paying customers who will tell us what “high-quality” pictures look like. And as we’ve consistently seen with a century of cinematic innovation—from color, widescreen and surround sound to 3D, 4K and high frame rates—“reality” is very much in the eye of the beholder.