Canon T2i/550d HDR Video is Coming
For the last six months, I’ve been obsessed with HDR photography (see my HDR photography work here) and am now obsessed with making HDR video a reality. But I wanted to make it a relatively simple and painless process (although, with HDR, it is rarely simple and painless), with a reliable and streamlined workflow. It took a few days of experimenting, but I think I’ve now concocted a pretty good cocktail for extracting HDR video from the Canon EOS Rebel T2i/550d DSLR. Why the T2i? Because it’s the only DSLR I own, and I love the challenge of getting as much image out of an $800 prosumer camera as I can. I’m also a big proponent of the “rebel without a crew”, “million dollar look on a thousand dollar budget” mentality, both for my own work and the work of others.
Up until now, creating HDR video (or at least giving an 8-bit compressed image a tone-mapped HDR look) was next to impossible. So what are the solutions? That starts with a basic understanding of HDR photography, which I won’t get into here. But, at the bare minimum, you need at least two exposures for every HDR frame: one overexposed and one underexposed. You then combine the two exposures to create an 32-bit HDR file, which you then “tone-map” with popular programs like Photomatix or Photoshop. (For tons more info and great resources on HDR photography, please visit Trey Ratcliff’s excellent site, Stuck In Customs.)
So how do you get two exposures with video? You don’t. You get one and only one constant exposure, shot at a particular frame rate, aperture, shutter speed, etc. On the other hand, the option for HDR video does open up a bit with the introduction of the Arri Alexa, which can capture 14 stops of latitude(!), and the very popular Red One/Epic/Scarlet. The Red Epic purportedly has an HDR feature capable of 18 stops of dynamic range(!!). These are exciting developments indeed and certainly open the door for real HDR video. But, 1) cost is working against you (as these rigs will run you north of $20,000), and 2) YOU STILL HAVE TO TONE-MAP THIS STUFF! What is tone-mapping? Read up on it here.
And here’s where we need to make a distinction between HDR and tone-mapping. Better minds than I can explain the difference, but, basically, HDR is a 32-bit FILE, while tone-mapping is what gives you that crazy/cool/amazing HDR LOOK. This “HDR Look” is what I, and most HDR aficionados, are obsessed with–not file formats. But the two terms get confused and swapped and then they lose their relevance. So, it’s super cool to have an HDR feature on the Red Epic, but you STILL HAVE TO TONE MAP THAT S#*T! And I’m not aware of any video tone-mapping software except Atlas, but it only runs on a PC, and I’m not sure how good the effect really is. And tone-mapping’s the hard part. It’s really at the heart, and art, of HDR photography. . . . But, the guys over at Soviet Montage, impressively, pulled it off. Here’s how they did it:
Video is captured on two Canon 5D mark II DSLRs, each capturing the exact same subject via a beam splitter. The cameras are configured so that they record different exposure values, e.g., one camera is overexposed, the other underexposed. After the footage has been recorded, we use a variety of HDR processing tools to combine the video from the two cameras, yielding the clips you see above.
Okay, this is spectacularly awesome, and I applaud Soviet Montage’s initiative and determination to get this done. But, they’ve posted nothing since, and have yet to explain their post-production workflow. 😦 This leads me to believe that their process is complicated (Two 5Ds hooked to a beam-splitter? Ugh.) and not very actionable in a real-world setting, although I could be completely wrong once I see the workflow. . . . I needed something better. I needed something 1) cheaper 2) less complex and 3) JUST AS COOL-LOOKING. That 3rd part is the really hard part.
The humble $800 Canon T2i does NOT, in fact, have an HDR video feature and will NOT give you 18 stops of dynamic range. In fact, it’s dynamic range is pretty limited and the image is crippled (like most current DSLRS) with line-skipping, pixel-binning, moire, aliasing, and various video noise/artifacts. But, I love these cameras, and they truly are a revolution in filmmaking. For $800, it’s almost criminal what you can pull off with the Canon T2i and the right lens. I’ve shot some of my best pictures and video on the T2i, and for all its drawbacks, it kicks every other video camera’s ass. Period. And there’s all sorts of reasons for that, but even the fact that you can attach an L Series Canon lens to a
$800 $700 camera with a SUPER 35-SIZED SENSOR is downright outrageous. Outrageous and so, so sweet for us filmmakers.
All of this is a big lead-up to the central question: how do I create HDR tone-mapped images from 8-bit T2i video (which is compressed to hell, has visible moire, and nasty aliasing)? I wasn’t sure at first, but now I am. Check out the screen grabs from my HDR video tests. These are NOT tone-mapped HDR photographs. These are from actual T2i footage that I shot over the last year. And the workflow and method I’ve devised is actually fairly realistic and workable, all for under $800, with no beam-splitters, no fancy rigs, etc. Check them out! I will have my HDR video test up very soon, if not in the next day or so. Once I get some feedback on the test video, and if there’s enough interest and people think it looks cool enough, I’ll do a post on my Canon T2i HDR Video workflow–all with average footage, straight out of the camera. I’m pretty excited about all this, so stay tuned, and in the meantime, go out and shoot some video/pictures already! ;0)