How Many Megapixels Did Avatar Need?
January 25, 2010
So, this new movie premiered a little while ago. You might have heard about it. The title was Avatar.
The mixture of live action and computer graphics sent reviewers into a hyperventilating frenzy. Even those who thought the story was a bit zero-dimensional found its imagery “dizzying, enveloping, vertiginous” and “epochal” among a bunch of other adjectives.
It was also legendarily expensive to create. Depending how you figure it, developing the technology and then completing the film probably went north of 300 million dollars.
So for shooting the live-action sequences, Cameron probably used some pretty high-end gear—right?
It might surprise you learn that those astounding, compelling images were shot using 2.2 megapixel cameras.
I’m not making this up. Avatar’s 3D camera rigs were developed by Cameron’s director of photography Vince Pace. In a fascinating article, he talks about the technology, and mentions that most of Avatar’s live-action 3D shots were done with pairs of Sony F950 HD video cameras. Download the brochure, and you can confirm that these models use (three) 2.2 Mp sensor chips (one for each RGB channel)*.
This might be less surprising when you consider that “full” HDTV is also not that many megapixels. Go ahead, multiply 1080 by 1920 (I’ll wait). Just a hair over two million, no?
Yet we all seem to feel that 2 Mp looks pretty darn nice, even when blown up to a 52″ screen.
Typically, computer graphics for theatrical releases are rendered at a what the industry calls “2K” resolution. This means 2048 pixels across the frame width. The vertical pixel count varies, depending on the aspect ratio. But for 16:9 proportions, it’s under 2.4 megapixels total.
Let that sink in for a moment. An industry that spends billions of dollars creating sock-o imagery, intended to be seen at billboard dimensions, thinks two megapixels is fine.
Oh yes, but won’t they kick that up even higher, the minute new technology permits?
Well, perhaps. There is some movement in Hollywood to introduce “4K” as a new standard. This means 4096 pixels across the width of the frame. District 9 was shot in 4K (despite the dearth of theaters so far which can project 4K). And CG films are sometimes rendered in 4K for IMAX release.
That pushes you up to around 9 megapixels per frame.
So you would imagine that James Cameron, who adores whizzy new imaging technology like no one else on earth, would be all over 4K.
Ah, actually not. Towards the end of this interview in Variety, Cameron says that, “4K is a concept born in fear [….] I would vastly prefer to see 2K/48 frames per second.” (Today’s film standard of 24 frames per second has trouble showing fast motion smoothly.)
Nine megapixels? Cameron doesn’t need it.
*Yes, this means the camera resolves color edges better than a 2.2 megapixel Bayer-filter sensor. But what our eyes mostly care about is the luminosity resolution.