Lytro's new light field camera

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Sabre
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Lytro's new light field camera

Post by Sabre »

Toms
Lytro today unveiled its second so-called light field camera, a system that lets you refocus a picture after it has been taken. The Illum is an upgrade from its predecessor, and you can pre-order it now for $1,499 (retail $1,599 after July 15).

You may never have heard of light field cameras, since the technology has mostly been limited to labs and specialized studios until Lytro brought it to consumers in 2011. As its name suggests, a light field camera captures the entire light field it sees, and it can record not just static details but also light rays and the direction in which they are moving.


Using companion software (on PC/Mac) or via the LCD touchscreen on the camera's back, you can choose a different focal point on your picture after it's been shot, build custom animations, and export your images into common formats such as JPEG. With a special plugin, people can interact with your pictures on their browsers by clicking to choose their own favorite perspective. The camera can also help create 3D graphics, and let you select tilt and perspective shifts as well as adjust depth of field (how much of the photo is in focus).

...
Will be interesting to see this tech evolve!
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Re: Lytro's new light field camera

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Lytro may have just saved it self...

http://petapixel.com/2016/04/12/lytros- ... en-screen/

They finally found the question that their technology is the answer to - how do we give ourselves more control in post for cinema? CG was the best option, now it may be this.
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Re: Lytro's new light field camera

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On one of the pans I noticed the shadow behind the figure changing relative to the figure as if the two were not connected (which, given how the camera captures data, they likely are not). However, it created a depth issue that looked flat and unreal. I suspect it is the sort of thing that can be corrected, but the fact that they didn't in the demo makes me think that it is not easy. The second is related to the first, that of light sources. I have watched demos of multi aperture cameras and they all have issues with multiple light sources. As I understand it, a lenses focal length or depth of field is limited to the available light. If the subject is well lit, there will be a wide depth of field available, less so in dimly lit areas. Less light, less data. So any transitions from a well lit to low lit area creates artifacts. Usually blocky areas with no data to extrapolate. Apparently this is not an issue that can be solved by throwing more megapixels at it. I don't know if these issues will be resolved as the technology evolves, or if there is really no fix and band aides will have to be developed.

All that said, I am very VERY impressed at how far this has come in just the last few years. And it is possible this will be THE way motion capture is going. At least on the high-end for movies.
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Re: Lytro's new light field camera

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I think what you're getting at is the relationship between apeture and depth of field. Apeture gets bigger (numerically smaller F/, which lets in more light) and the depth of field gets shorter, apeture gets smaller (down to a pin hole, letting in less light, numerically larger F/) and the depth of field gets longer. Depth of field and focal length are different but related (roughly, longer focal length equals shorter depth of field). Some math at the wiki page.

So the relationship is actually backwards from what you say - better lit = smaller apeture to control (limit) exposure = shorter depth of field. This isn't always the case, you can mess with ISO or shutter time to control exposure instead, but its the easier thing to change (ISO can give you graining and shutter time can result in blurring if its too long).

I think you're seeing two kinds of artifacts. Frame attached. 1) At the back edge of the pool table (and the edges of the scene) you're seeing black - these are areas the camera couldn't see (it doesn't see around corners, a light ray still has to "bounce" from each point in the scene to some part of the lens and get imaged on some part of the sensor) so it doesn't have any data to fill in. 2) at the left edge of her face you're seeing some ghosting, this is probably a combination of compression and algorithm glitch.

So yea, definitely still work to do, but its gonna be pretty cool to follow.
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Re: Lytro's new light field camera

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Just putting this here since I think it's important in this discussion:
Image

You all have fun with the camera discussion... I'll just admire the tech and look forward to the results with it :)
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Re: Lytro's new light field camera

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Yea, thats the idea. That is in every photography book and class. I don't like it (neither does this guy http://www.nickcarverphotography.com/bl ... s-useless/), its ok from a conceptual standpoint but it doesn't really help you develop a sense for it. This interactive tool is pretty good - http://www.exposuretool.com/ And this Canon one isn't bad for explaining things - http://www.canonoutsideofauto.ca/play/
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Re: Lytro's new light field camera

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So the relationship is actually backwards from what you say - better lit = smaller apeture to control (limit) exposure = shorter depth of field. This isn't always the case, you can mess with ISO or shutter time to control exposure instead, but its the easier thing to change (ISO can give you graining and shutter time can result in blurring if its too long).
Actually, I don't think we are not talking about the same thing. I probably wasn't clear by using the term "depth of field" which would indicate a specific aperture setting. I do not think that is what is happening. I think it is the way the image is "layered" (for lack of a better word) in an attempt to allow image/camera "shifting" (left, right, up, and down). In real viewing the "shifts" would change the viewer's angle to the subject and the light source. But in this instance it can't. The light source is unchangeable. The camera can create a "sense" of it with the overlaid "layers" but when the shadows should be changing with the viewer's perspective they can't. There is no data available. I'm not saying it's a big deal or it can't be fixed. But I suspect it is done in post production and requires some time and effort, and may be more art than science. Again, this is awesome stuff and I'm very impressed with how far this has progressed.
Yea, thats the idea. That is in every photography book and class. I don't like it (neither does this guy http://www.nickcarverphotography.com/bl ... s-useless/), its ok from a conceptual standpoint but it doesn't really help you develop a sense for it.
I'm with Nick/Jason on this one. It's good to understand those relationships, but they are becoming less important in the world of digital photography. For example, ISO becoming a bit irrelevant as the sensors get better. In the days of film (and early digital) the higher ISO (or ASA / DIN) was guaranteed to be more grainy with less detail (information). It was an accepted limitation in film, but as digital sensors get better and better that is becoming less the case. Setting a high-end digital camera ISO to 100 does not mean 4 times the image quality/detail/information than setting it at 400. Yes, it will still have an affect on the shutter speed and aperture settings, but the camera sensor does not "need" for the user to "tell" it what it's light sensitivity is. When it comes to digital motion capture, things get even more complicated with the lens/scanner interface.
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Re: Lytro's new light field camera

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drwrx wrote:Actually, I don't think we are not talking about the same thing. I probably wasn't clear by using the term "depth of field" which would indicate a specific aperture setting. I do not think that is what is happening. I think it is the way the image is "layered" (for lack of a better word) in an attempt to allow image/camera "shifting" (left, right, up, and down). In real viewing the "shifts" would change the viewer's angle to the subject and the light source. But in this instance it can't. The light source is unchangeable. The camera can create a "sense" of it with the overlaid "layers" but when the shadows should be changing with the viewer's perspective they can't. There is no data available. I'm not saying it's a big deal or it can't be fixed. But I suspect it is done in post production and requires some time and effort, and may be more art than science. Again, this is awesome stuff and I'm very impressed with how far this has progressed.
You're right, the light source is unchangeable. The light coming from the source, reflecting (-ish, absorption and reemission in most cases) off the object and going to the camera is often thought of as a ray, a single infinitely small line. In reality there is some slop in the system - the light source isn't an infinitely small point, the atmosphere causes some diffusion, each point on the object reflects off at multiple angles, etc. What makes a light field camera different is that it can measure the angle of the incoming light at each pixel, in addition to the amplitude of the light. This doesn't give you the ability to see around corners (like the black edge of the pool table) and it doesn't let you move the original light sources, but it does give you some extra information for algorithms to work with that makes the camera movement more realistic.
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Re: Lytro's new light field camera

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:popcorn:
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