Camera Labs

Hi folks,

I came across a new, to me at least, take on how to manage the size of the electron well associated with each pixel in a camera sensor. For those to whom the concept is new, the electrons which are photoelectrically released as light strikes the camera sensor are stored in a manner analogous to water drops being captured in a bucket. When the exposure is finished the electrons are "read" (how much water is in the bucket) and the bucket emptied.

Anyway, it seems that Aptina has come up with a way of varying the size of the bucket. Check out their video DR-Pix Technology. I'd highly recommend watching this video at 720p resolution and full-screen. There are some technical presentations to get past but by about three minutes into the video we start seeing some sample images. It's to get the best from those that I recommended 720p and full-screen.

It's difficult to know how good this new technology really is as one can only compared shots taken with Aptina sensors. So far as I can tell their sensors aren't used in any current DSLRs but maybe I just haven't looked carefully enough. But at face value this technology appears to work really well with startling improvements in high ISO image noise.

Bob.

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OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

In a quick scan of the video and white paper, it sounds like an interesting method that allows read out noise reduction in low light, OR the switching in of "bigger buckets" to get more headroom where there is a lot of light. As far as I can tell, this only improves the noise, but it doesn't increase dynamic range or sensitivity.

The question I have is how much space does this extra circuitry need to implement? Is there a pixel size "sweet spot" for its implementation? e.g. does it work better for small pixels or big ones? Or maybe it doesn't matter at all...

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Canon DSLRs: 7D, 5D2, 1D, 600D, 450D full spectrum, 300D IR mod
Lenses: EF 35/2, 50/1.8, 85/1.8, 135/2+SF, 28-80 V, 70-300L, 100-400L, TS-E 24/3.5L, MP-E 65, EF-S 15-85 IS
3rd party: Zeiss 2/50 makro, Samyang 8mm fisheye, Sigma 150 macro, 120-300 f/2.8 OS, Celestron 1325/13
Tinies: Sony HX9V.

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As far as I can tell switching in the "bigger bucket" should allow increased dynamic range as one can store more electrons but that only works if the read-out noise, or any other associated noise, doesn't increase proportionally.

Like you I didn't hear any explanation of why the sensitivity would be improved. Improving the signal to noise ratio is one thing but I'd always rather assumed that the quantum efficiency of the detector is fixed at birth.

Bob.

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OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

If you switch in the "bigger bucket" yes you can deal with more photons, but then you start to lose the shadow areas in noise. So I don't think it improves dynamic range there. I'll have to look at it again in more detail when I have time.

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Canon DSLRs: 7D, 5D2, 1D, 600D, 450D full spectrum, 300D IR mod
Lenses: EF 35/2, 50/1.8, 85/1.8, 135/2+SF, 28-80 V, 70-300L, 100-400L, TS-E 24/3.5L, MP-E 65, EF-S 15-85 IS
3rd party: Zeiss 2/50 makro, Samyang 8mm fisheye, Sigma 150 macro, 120-300 f/2.8 OS, Celestron 1325/13
Tinies: Sony HX9V.

my head is all electroned out, had a two hour lecture today on the subject during my photography theory class.

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Mark Osborne
My life through an iPhone