81–90 of 98 posts
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Yes, but why can’t the camera do it continuously? Film at 240fps and provide a 60fps output with 10bit color depth.
Because the images would look funny. Imagine you're capturing someone running - at frame 1, they would be at position x, and at frame 2, they'll be at position x + 1. If you try to stack them together, you'll get a weird ghosting effect.
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Worth noting that those "HDR" televisions are still only Rec709 which is limited to about 6 stops of dynamic range. Sure some are approaching rec2020 color gamut, but we're still cramming all that gamma down into 6-9 stops. Even a consumer DSLR can shoot 12. I work in post and have moved our workflow over to the Academy Color Encoding Specification (ACES) which supports up to 27 stops (more than the eye can see which…
Interesting, will look into ACES. What do you use for the files, openEXR? Yep first "HDR" tv's will be rec709 but higher DR is definitely coming, both to home TVs and cinemas (via super bright laser projectors) http://blog.abelcine.com/2015/03/06/high-dynamic-range-expla... I'm actually not convinced most people will want 5-100x brighter pictures than we currently have! Dynamic range of the human eye is also related…
As for file formats, it varies entirely on the show. Higher end, fx heavy shows tend to use DPX and occasionally openEXR while lower end shows are typically some flavor of ProRes (422HQ and 4444 being nosy common). DNxHD 175 or 220 are also occasionally used. Some people are trying to move to the new ProRes high quality (4444XQ or DNxHR).
Delivery specs for whatever network are almost always ProRes 422HQ 720p or 1080p. Features we'll output to DPX or TIFF which will be converted to DCP (JPEG2000) in the P3 color space (XYZ instead RGB or YUV).
I'm excited to see higher bitrates for delivery, but it's going to be a long time on the broadcasters end. They're wary to upgrade so soon - especially when a lot of people already have trouble telling 720p from 1080p.
The pictures using the "modulo camera" are definitely better quality, but don't look noticeably better than what I could do with a RAW from my camera and 2 seconds in Capture One or Lightroom adjusting the shadows and highlights.
The title here is terrible because over-saturation is an effect of poor tone mapping, which is inevitable if you want to display an HDR image in a low dynamic range display. An accurate title would be the end of over- exposed images, but why not just keep the original?
They're talking about the pixel brightness values getting saturated (255), not colour saturation. But I've never heard over- saturation being used to refer to brightness saturation - brightness is either saturated or not.
While such a thing is not very useful for taking pictures (pointing the camera at a static scene will generate no output at all) or videos (you don't get discrete frames, you get a continuous stream of differentiated pixels), it has a lot of potential for computer-vision tasks:
For one, as the camera only reports changes, only the interesting information is transmitted which greatly reduces computational load (eg. no need for "yes, that white wall is still there"-style calculations for every frame).
Secondly, because these changes are reported independently per pixel, they are very fast: Microsecond accuracy with a dozen or so uS delay are easily achievable. For comparison, a fast camera with 120 FPS (which will produce a lot more data to process) has an accuracy and latency of 1/120s = 8333uS. This also implicates that motion blur is basically nonexistent.
And thirdly, as absolute intensity doesn't matter, you don't have any problems with high dynamic range either.
The only downside is, that you don't really get a picture and most of the traditional computer-vision approaches are unusable ;)
But still, such a camera is very neat, even if you just track the movement of your mice or want to balance a pencil on it's head[2].
The real deal however is full vision based 3D-SLAM, which would allow for very fast and robust movement without any external help from motion capturing systems or expensive (in money, weight and power) sensors like laser scanners. AFAIK, we're not there yet (see [3] for some work in that direction), but that would bring pizza delivery with a drone directly to your desk quite a bit closer to reality...
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[1] http://www.inilabs.com/products/davis
[2] http://www.ini.ch/~conradt/projects/PencilBalancer/
[3] http://rpg.ifi.uzh.ch/research_dvs.html, also https://www.doc.ic.ac.uk/~ajd/Publications/kim_etal_bmvc2014...
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Because the images would look funny. Imagine you're capturing someone running - at frame 1, they would be at position x, and at frame 2, they'll be at position x + 1. If you try to stack them together, you'll get a weird ghosting effect.
Well, that ghosting effect is also called motion blur. If I integrate continuously, that is.
I had an idea similar to this that solved the oversaturation issue. Use 2 cameras. Have them at right angles to the shutter point, separated a few inches. At the T junction where the camera pointing would cross with the shutter area, put a prism there. The prism would give each camera 1/2 of the available photons. Now use any standard HDR processing technique.
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> This is a "computer scientists" understanding of photography, and this phrase alone can even be seen as "dangerous" by photographers. The actual headline of the article is actually more informative and less misleading than the subhead: "Unbounded High Dynamic Range Photography Using a Modulo Camera" In photographer's terms, they're referring to ending blown highlights (caused by filling the wells in a sensel) not s…
> There's a school of photography that basically lives and dies by over-saturating images (e.g. http://kenrockwell.com ) and they'd likely have a cow over the headline, but understand and be totally onboard for the actual goal. Actually, I suspect that even that crowd, after the initial shock would be absolutely on board. This would mean that no longer would the sensor control how the high-end clipping happens, but n…
To emulate film stock we need a solid 14-bits of Dynamic range (while DxO says the D810 has it, the article below says 11-bits, but the best video cameras are getting there):
http://wolfcrow.com/blog/where-cameras-stand-in-dynamic-rang...
Ideally we'd get something like this AND capture polarization data as well (per the recent Olympus patent). Then you can apply polarization and exposure correction in post.
Earlier quoted context omitted.
> This is a "computer scientists" understanding of photography, and this phrase alone can even be seen as "dangerous" by photographers. The actual headline of the article is actually more informative and less misleading than the subhead: "Unbounded High Dynamic Range Photography Using a Modulo Camera" In photographer's terms, they're referring to ending blown highlights (caused by filling the wells in a sensel) not s…
> BTW: assuming they can do this stuff, they presumably can read the sensor pretty darn fast What's funny is that the iPhone (and a high end Android phone) has way faster processors than your typical $10.000 DSLR.
A good smartphone can capture 4K video or 20fps 8MP or whatever off the sensor — both around 160MB/s. A $10k DSLR is handling 16MP at 11fps — that's around 300MB/s (remember that the DSLR is handling 14-bits per sensel).
The interesting thing is that if you look across the camera lineups, there's almost no difference in CPU between a $300 consumer camera and a $10k professional (there is a big difference in RAM - the DSLR is able to store 50+ uncompressed images in RAM (let's say 3-4GB), while the phone or low end camera processes them into JPEG before storage.
> No more will photographers or even ordinary people have to fumble with aperture size and exposure length. This is a "computer scientists" understanding of photography, and this phrase alone can even be seen as "dangerous" by photographers. There's more to aperture size and exposure length than "how much light reaches the sensor", like focus, depth of field, motion blur and bokeh, to name a few, that is not aknowled…
I'm surprised no one in the comments so far has used the word "clipping", which is what the real breakthrough here is in. I've been doing street photography somewhat seriously for about five years now, and always shoot full-manual: I rarely have problems with motion blur because I control the shutter speed; I rarely have problems with focus because I use assisted manual; the only thing that gets me with any regularit…
If you're interested, try Tri-X for BW and Fuji Velvia 50 for color. Any late 70s Nikon will do well as a camera, the old 50mm f1.4 is particularly good and cheap. Tri-X is best developed yourself, but the Velvia needs sending to a lab that specializes in positive film development.