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HDR Video a Reality
akaru writes "Using common DSLR cameras, some creative individuals have created an example of true HDR video. Instead of pseudo-HDR, they actually used multiple cameras and a beam splitter to record simultaneous video streams, and composited them together in post. Looks very intriguing."
HDR
Focus Stacking
Panoramic Stitching
All in the camera, all 1-button easy to use, and all at once.
The trumping technology to follow: 3D-HDR Video!!
There's a spot in User Info for World of Warcraft account names? Really?
C&P from the linked page (assuming a /.'ing imminent)
HDR demo @ http://vimeo.com/14821961
Press Release:
HDR Video A Reality
Soviet Montage Productions releases information on the first true High Dynamic Range (HDR) video using DSLRs
San Francisco, CA, September 9, 2010: Soviet Montage Productions demonstrated today the first true HDR video sourced from multiple exposures. Unlike HDR timelapse videos that only capture a few frames per minute, true HDR video can capture 24 or more frames per second of multiple exposure footage. Using common DSLRs, the team was able to composite multiple HD video streams into a single video with an exposure gamut much greater than any on the market today. They are currently using this technology to produce an upcoming film.
Benefits of Motion HDR
HDR imaging is an effect achieved by taking multiple disparate exposures of a subject and combining them to create images of a higher exposure range. It is an increasingly popular technique for still photography, so much so that it has recently been deployed as a native application on Apple’s iPhone. Until now, however, the technique was too intensive and complex for motion. Soviet Montage Productions believes they have solved the issue with a method that produces stunning–and affordable–true HDR for film and video.
The merits of true HDR video are various. The most obvious benefit is having an exposure variation in a scene that more closely matches the human eye–think of filming your friend with a sunset at his or her back, your friend’s face being as perfectly captured as the landscape behind them. HDR video also has the advantage of reduced lighting needs. Finally, the creative control of multiple exposures, including multiple focus points and color control, is unparalleled with true HDR video.
“I believe HDR will give filmmakers greater flexibility not only in the effects they can create but also in the environments they can shoot in” said Alaric Cole, one of the members of the production team, “undoubtedly, it will become a commonplace technique in the near future. ”
Contact:
Michael Safai
Soviet Montage
201 Spear Street #1100
San Francisco, CA 94105
1 415 489 0437
mike@sovietmontage.com
Those who can, do. Those who cannot, sue.
Can anyone give a brief rundown on what HDR is? I know it stands for "high dynamic range", but as someone who knows nothing about photography, it means nothing to me. What it has to do with overexposure/underexposure (to which the video refers)? Why is it harder to do with video than still images?
I've been a long-time fan of HDR photography, and was just thinking about ways that HDR could be implementing in video camcorders as well. Personally I'd like to see a correctly-exposed stream mixed in with the other two, as is common in photography, but even without that the effect is pretty darn cool.
By the way, in case any camcorder manufacturers are watching, consider this idea: make a video camera with three (or more) times the required number of sensors for the resolution you want to record at. Set the logic in the device up to use three unique sets of sensors inside to pick up three different sets of images, at differing exposure settings. Then have them saved separately so that they can be integrated later on for various editing effects - or have a mode where they are integrated on-the-fly for easier use by non-professionals. I imagine it would be expensive to make such a complex sensor and camera, but it might be easier to manage than multiple cameras as the folks in the article did.
William George
Wasn't the first HDR video camera back in 1993? Granted, they called it Adaptive Sensitivity back then.
Cool
In soviet Russia, God creates you!
The technique is promising, but the provided example video does not demonstrate a true advantage it has over conventional cinematography. They filmed with two cameras, one overexposing one underexposing, but they don't have one with the right exposure to compare with the composed HDR images. The city scenes are filmed at daylight, without any areas of high contrast that would make a high dynamic range necessary. The same with the people example, they even overdid it to give it a vibrant effect, making it more of an artistic tool than capturing shadows and lights naturally.
They should make a short film with city nighttime and desert scenes, that should be impressive. They should also contact director Michael Mann, he would jump at the opportunity to film HDR.
This is so much better than 3D technology. It's even better than high definition video. This is actually the process of creating better images. I am actually really excited about this!
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The bright spots are indeed an artifact of the HDR process -- partulcarly the tone-mapping algorithms. On its own, HDR is basically a method of capturing intensity values that would otherwise fall above or beneath the threshold of a camera's sensitivity. The problem is, when yo do that you end up with image data that can't be completely represented within the gamut of a printer or a screen. You could simply display a "slice" out of the data, which results in a regular images at whatever exposure setting you've chose, or try to "compress" the tone values into your available gamut, which results in a washed-out appearance. This is where tone-mapping comes in. What tone-mapping does is try to compute the correct exposure levels on a per-pixel basis, by comparing its intensity relative to nearby pixels. Ideally, this results in shadows being brightened to the point where you can see detail in them, and blown-out highlights brought toned down (analogous to "dodging" and "burning" in terms of old-school darkroom film processing -- the dynamic range of film is much higher than that of photo paper).
In practice, though, you end up with weird highlights around dark areas, like the ones you saw around the man's arms, because the tone-mapping algorithm is trying to maximize the local contrast in the image. It's brightened up the coat, and so it also brightens nearby pixels to compensate for the reduction in contrast. Some people try to adjust the algorithms to minimize this effect, while others try to maximize it for dramatic effect, or even an oversaturated, impressionistic look -- it's largely an artistic choice, though when done badly it can also be a sign of amateurism. Still others will manually composite multiple exposures to get the benefits of HDR imaging while avoiding its side effects entirely,
The Wikipedia article on tone-mapping goes into great detail on the different approaches to HDR photography, if you're interested.
You're seeing a moving halo effect. Most tone-mapping processes have trouble with dark on light transitions. Basically, in an attempt to 'smooth' out the transition between lightening/darkening, you get the lightening effect bleeding from the dark regions to the lighter regions creating a halo. If you watch the starting sequence with the buildings, if you look at the right side with one building in the foreground, and the dark side of another building in the background, you can once again see the halo effect. Just go google around HDR images, and you'll see it everywhere. It's very hard to get rid of, and simply put, if you run any tone-mapping process on default, you'll end up with them.
It's basically the result of the software not being able to tell with confidence where the boundaries between higher/lower exposure is, so instead it assigns an approximate that "plays it safe" in one direction, and then smears out the boundary. Basically photoshop's magic selection wand + feathering.
Incorrect, it's true HDR recording. The process of viewing it on LDR/SDR monitors is tone-mapping, which over the years has been tuned to represent the best known science of what the eyes actually see at once - our retinas already make us susceptible to only being able to view certain ranges of light at a time.
In other words, more information is being recorded than your eye can see at once, and you're complaining because when you see it, all that information isn't there? That's a pedantic, unsolvable contradiction.
A true HDR *display* (unfathomably difficult to imagine, I won't begin to go into the problems with the source for all the light being in one location, while other light is also hitting the eye from the real-world outside of the display, making visual processing of the HDR display massively erronous), would offer no advantage to a tone-mapped image, as your eye still can't see more than a certain range at any given time.
Tone-mapped SDR images actually produce images with more visible detail *at once* than the eye can distinguish *at once*. Sure, the eye can do things the still image can't, like focus somewhere else, shield out certain bright or dark parts, and readjust automatically to what you're now viewing - I'm not claiming tone-mapping will ever produce as much variance as the eye is capable of - but it DOES bring to light more detail in HDR recorded scenes than the eye could otherwise see at once looking at the same scene.
"The true measure of a person is how they act when they know they won't get caught." - DSRilk
With frankencamera you could do HDR and a lot more things in an "intelligent" camera with software. In fact the first implementation in a mass consumption device was in the N900, it takes several photos, regulates exposition and other parameters to make that photo in a more parametrizable way that the iphone could do. But not sure if that would be enough for HDR video, if needs that the input, in real time, have different something at hardware level. In that case maybe something like this 3D camera would be needed. And could give some meaning to such devices... not only shooting in 3d, but in HDR video.
Especially the part with the guy talking, made me think...
So someone's found a way to make real life look life Half-Life 2 Episode 2?
I'd rather have someone respond than be modded up.
For the third of the Fast and Furious movies, we had to film at night in the spectacular Shibuya Square in Tokyo, with its many animated billboards and video screens. I really wanted to get an HDR film of the billboards.
For the driving green-screen sequences of the film, we had built a plate to mount three cameras, at 0, 45, and 90 degrees, to shoot panoramas driving down the street. To get the nodal points closer together, we had the cameras facing toward each other, with the lenses almost touching. It worked wonderfully.
By taking the center camera out, and replacing it with a beam-splitter, we had a down-and-dirty HDR rig using the other two cameras. Now, this was HDR on film, not video -- but film already has a very high dynamic range -- so two cameras with very different effective exposures gave us a tremendous dynamic range. In the 'normal' exposure all of the brighter signs were blown out, but on the beam-splitter camera you could see all the details of the structure of the lighted billboards. Quite cool.
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