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http://www.lytro.com/



Pretty interesting. The technology allows focusing via software AFTER shooting.

oppitronic

[quote name='Klaus' timestamp='1308741419' post='9398']

http://www.lytro.com/



Pretty interesting. The technology allows focusing via software AFTER shooting.

[/quote]



Very interesting, and a bit sad, as it would destroy all the fun of photography.

Guest

Destroy all the fun? I don't think so!

Has photography killed painting? Not so much!

Has video killed the radio star? Um ...



Ciao, Walter
I see how it works. Each sensel is directional. Instead of having a microlens on top of each sensel that steers and blends light together, the data is recorded separately. Cool!



I wonder how many different directions it records? I wonder if you can change dof? I wonder if the number of directions has a bearing on dof?
It doesn't actually record different directions, to be very honest, at least not to a very strong degree. It does capture at different distances in the focal plane, likely by having a slightly 3D type design of sensor (not a lot of displacement needed at the sensor side). Which is also why it can do 3D, and also why it probably doesn't do extreme high quality yet.



It's an interesting concept, based on a development in the 1990s, if I am not mistaken. Canon also showed something similar, which also can record video, a bit over a year ago, I think.



BTW, here is more and an interview with the founder of Lytro:

[url="http://techcrunch.com/2011/06/21/lytro-launches-to-transform-photography-with-50m-in-venture-funds-tctv/"]TechCrunch - Lytro[/url]



Kind regards, Wim
[quote name='wim' timestamp='1308764617' post='9412']

It doesn't actually record different directions, to be very honest, at least not to a very strong degree. It does capture at different distances in the focal plane, likely by having a slightly 3D type design of sensor (not a lot of displacement needed at the sensor side). Which is also why it can do 3D, and also why it probably doesn't do extreme high quality yet.



It's an interesting concept, based on a development in the 1990s, if I am not mistaken. Canon also showed something similar, which also can record video, a bit over a year ago, I think.



BTW, here is more and an interview with the founder of Lytro:

[url="http://techcrunch.com/2011/06/21/lytro-launches-to-transform-photography-with-50m-in-venture-funds-tctv/"]TechCrunch - Lytro[/url]



Kind regards, Wim

[/quote]

The idea behind lightfield capture is to capture the direction of the light. Not focal planes.



This is the reason why one can look behind subjects, somewhat, and can vary DOF and focal plane during the visualization of the data.



How exactly they capture the direction vector (together with intensity and colour) is not disclosed yet. Nor how high (or low) the data density will be.



*edit:



It is explained how the directional vectors are gathered, in this thesis:

http://www.lytro.com/renng-thesis.pdf



Basically, if I understand correctly, a "conventional" sensor is used to capture many tiny images of the same scene, each image "fed" by its own micro lens.



This gives many images with views from slightly different viewpoints, with with the lightfield is being calculated.



The resulting lightfield is then used to compute the different focal plane projections when viewing the image.

arvydas

There is a nice article in Wiki about [url="http://en.wikipedia.org/wiki/Light_field"]light field[/url]. IMHO new camera should be more consumer-related implementation of already existent technology used in more specialized areas. However, is it more useful then, let's say, 3D camera is questionable - for really good performance price might be too high.



A.
[quote name='Brightcolours' timestamp='1308766431' post='9413']

The idea behind lightfield capture is to capture the direction of the light. Not focal planes.



This is the reason why one can look behind subjects, somewhat, and can vary DOF and focal plane during the visualization of the data.



How exactly they capture the direction vector (together with intensity and colour) is not disclosed yet. Nor how high (or low) the data density will be.



*edit:



It is explained how the directional vectors are gathered, in this thesis:

[url="http://www.lytro.com/renng-thesis.pdf"]http://www.lytro.com/renng-thesis.pdf[/url]



Basically, if I understand correctly, a "conventional" sensor is used to capture many tiny images of the same scene, each image "fed" by its own micro lens.



This gives many images with views from slightly different viewpoints, with with the lightfield is being calculated.



The resulting lightfield is then used to compute the different focal plane projections when viewing the image.

[/quote]

Thansk for that link - I just wish I had time to read it all <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='Big Grin' />.



It loosk liek thsi system uses a set of microlenses with one each for a group of pixels. The principle used for focusing is ray-tracing, I see, which, in a way, virtualizes the different focal planes required for different distances in the object plane(s).



Reading further, it looks like it therefore effectively uses an facetted eye approach - interesting, because effectively it stores a full image for each set of pixels served by a microlens, and it also means that this diminishes the effective resolution, approximately by the square root of the number of sensels per microlens. Each image then is indeed an image from a different light ray and angle.



I now understand why there will be consumer cameras first. 2.2 MP from a much larger sensel array is good enough for consumer pictures. In short, the focusing ability after the fact of such a system essentially delimits the resolution one can obtain. For obtaining higher resolutions, one needs very high MP sensors, ones that aren't used in commercial quantities yet (100 MP+).



Kind regards, Wim

finaldesignrb

[quote name='wim' timestamp='1308778016' post='9415']

For obtaining higher resolutions, one needs very high MP sensors, ones that aren't used in commercial quantities yet (100 MP+).

[/quote]

Am not so enthusiastic about the potential for fine photography with the lightfield camera either.



For example, by the time we have those 100 megapixel+ sensors, the performance of the sensors and electronics and focusing gadgets and ultrasonic motors will be so high that there will be other ways of real fast focus stacking. To derive images with some of the features of the lightfield camera. Movies made up out of lots of images taken while racking the focus of a regular lens, for example. Not exactly what the lightfield camera does, but a way in software with fast hardware to give you a little movie that you can click through to get to various images taken at various sharp-focus planes.



And the great thing about the focus-stacking is that it will happen with equipment that will of course still be perfectly usable to take ordinary, superb 100 megapixel pictures. 100 megapixel pictures naturally will have super high ISO potential because you can, say, downsample them 16X to 6 megapixels, with a quarter of the noise.



Having said this can see "potential" for lightfield cameras in some industrial imaging, and low-end point and shoot applications. Or maybe not, because if there's some need for what the lightfield does, regular camera makers once again could hustle up with their own focus racking technology.

Guest

[quote name='RussellB' timestamp='1308952356' post='9485']

Am not so enthusiastic about the potential for fine photography with the lightfield camera either.



For example, by the time we have those 100 megapixel+ sensors, the performance of the sensors and electronics and focusing gadgets and ultrasonic motors will be so high that there will be other ways of real fast focus stacking. To derive images with some of the features of the lightfield camera. Movies made up out of lots of images taken while racking the focus of a regular lens, for example. Not exactly what the lightfield camera does, but a way in software with fast hardware to give you a little movie that you can click through to get to various images taken at various sharp-focus planes.



And the great thing about the focus-stacking is that it will happen with equipment that will of course still be perfectly usable to take ordinary, superb 100 megapixel pictures. 100 megapixel pictures naturally will have super high ISO potential because you can, say, downsample them 16X to 6 megapixels, with a quarter of the noise.



Having said this can see "potential" for lightfield cameras in some industrial imaging, and low-end point and shoot applications. Or maybe not, because if there's some need for what the lightfield does, regular camera makers once again could hustle up with their own focus racking technology.

[/quote]

So potentially any SLR with live view (contrast AF) could do that - simply by recording during AF. If it's capable of taking 1080p video, 2mp "multi image" would be recorded in less than a second (I'm pretty sure 20-30 frames is more than enough to cover whole focus range, except macros of course).
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