Archived posting to the Leica Users Group, 2008/07/16

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Subject: [Leica] 50 Meg Kodak sensor - maybe this is what's happening behind the doors at Solms:
From: faneuil at gmail.com (Eric Korenman)
Date: Wed Jul 16 07:28:55 2008
References: <487E03C4.5020605@sympatico.ca>

again-  hopefully this will push 22 and 39 MP backs into a more
affordable* range soon.

Eric

*depends on what you mean by affordable. But $32,000 isn't !

On 7/16/08, Vick Ko <vick.ko@sympatico.ca> wrote:
> 50 Meg Kodak sensor - maybe this is what's happening behind the doors at
> Solms:
>
> http://www.technologyreview.com/Infotech/21088/?nlid=1211
>
>
>  Pushing Pixels
>
> Kodak's latest sensor enables digital cameras to enter the 50-megapixel
> range.
>
> By Duncan Graham-Rowe
>
> Last week, Kodak launched the first ever 50-megapixel camera sensor. While
> such high resolution goes beyond the needs of most consumers, for
> professional photographers the new sensor will enable photographs to be
> taken at an unprecedented level of detail.
>
> For example, in a picture taken of a field one-and-a-half miles across, the
> sensor would make it possible for a viewer to detect an object measuring
> just one foot across.
>
> This sort of resolution is only really essential for and targeted at
> high-end professional photography, in which high-quality images often need
> to be blown up large. But it could also be useful for some other
> applications, such as aerial photography as used for services like Google
> Earth. "The ability to have more pixels lets the plane fly higher, so you
> don't need as many pictures," says Mike DeLuca
> <http://michaeldeluca.pluggedin.kodak.com/>, marketing
> manager for Kodak
> <http://www.kodak.com/eknec/PageQuerier.jhtml?pq-path=2/6868&pq-locale=en_GB&_requestid=6900>'s
> Image Sensor Solutions, based in Rochester, NY.
>
> The sensor, which produces an array of 8,176-by-6,132 pixels, further 
> closes
> the gap between traditional film and digital photography. "We're really
> close to how film was operated," DeLuca says. "It's very close." Now, he
> says, it's just a matter of the photographer's personal preference.
>
> Normally, the smaller you make a pixel, the poorer the quality, says Albert
> Theuwissen <http://www.harvestimaging.com/index.php?id=1>,
> a digital-imaging expert and founder of Harvest Imaging, based in Bree,
> Belgium. "That is true for consumer as well as professional devices." 
> DeLuca
> claims that in the case of Kodak's breakout sensor, new pigments actually
> increase the color quality rendered by the sensor, while other mechanisms
> enable the pixels to be just as sensitive as larger ones--and yet they're
> processed faster than in previous designs. What's more, he claims that the
> new sensor uses less power than its predecessors. "Every solution or step
> that makes the sensor faster and less power hungry is a step forward," says
> Theuwissen.
>
> Kodak already has a sensor on the market with a resolution of 39 million
> pixels. But to further increase the resolution, the company had to not only
> reduce the size of each pixel from 6.8 microns to 6 microns, but also
> radically change the way that these charged coupled device (CCD) sensors
> work, says DeLuca.
>
> "It's relatively straightforward to make the pixels smaller," he says. But
> because these devices comprise much more than just light-detecting 
> elements,
> DeLuca says, they can suffer drops in performance if everything inside them
> is not shrunken along with the pixels.
>
> "Each pixel has multiple structures," he says. Some are designed to pass a
> charge from one pixel to the next, to enable the image to be read off the
> device. Other structures ensure that any excess charge produced by bright
> lighting conditions doesn't spill out into neighboring pixels.
>
> Another challenge is to maintain the dynamic range of the sensor--that is,
> its ability to detect light and dark simultaneously. In the sensor, this is
> basically a signal-to-noise issue, says DeLuca. "When you make the pixel
> smaller, there is less signal you are able to capture, because physically
> there is less ability to store electrons in that pixel. If we don't do
> anything else, what we end up with is a smaller signal with the same noise
> profile." To counteract this, Kodak has had to improve the amplifier at the
> output of the device, which reduces the noise.
>
> Also, by increasing the number of pixels, it becomes more challenging to
> access the information once it has been detected. "Fifty million pixels is 
> a
> lot of data
> <http://www.technologyreview.com/Infotech/21088/page2/#>,"
> says DeLuca, ," says DeLuca, and a photographer needs to be able to read it
> off the sensor in a reasonable amount of time.
>
> Until now, Kodak has used a process that involved dumping the information
> from one row of pixels onto the next and shifting the information along the
> row, reading it off at the edge, one pixel at a time. This is a relatively
> slow process, normally carried out two rows at a time. So to cope with the
> additional amount of data, the new sensor comes with four output channels 
> so
> that four times the amount of data can be read at once. This enables the
> sensor to increase the rate at which images can be captured from 0.9 to 1.0
> frames a second, even though more information is being captured. And yet
> this also allows the clock cycle at which the data is read off to be 
> reduced
> for each output, which further improves the signal-to-noise ratio.
>
> Power savings are achieved by the way that the sensor is reset before each
> picture is taken. This is carried out just before a shot is taken to ensure
> that there is no residual charge or electrical noise in the pixels that
> could reduce the quality of the new image. In previous sensors, Kodak has
> simply read out each of the pixels row by row, as if collecting the data 
> for
> a picture, but then it dumped the information instead of storing it. "What
> we've included now is a new structure in the pixel which allows all the
> pixels in the array to be cleared out in a single clock pulse," says 
> DeLuca.
> So instead of having to flush the entire sensor row by row, you flush the
> entire array in one go, he says.
>
> This dramatically improves the "click to capture" time--the delay between
> pressing the shutter down and the sensor capturing the image. "Instead of
> being milliseconds, it takes microseconds," says DeLuca. And in addition to
> saving time, it also reduces the power that is required to perform a reset.
>
> This technology doesn't come cheap. The sensor alone will cost at least
> $3,500. But that doesn't appear to have put off one camera manufacturer.
> Hasselblad
> <http://www.hasselbladusa.com/promotions/50-promotion.aspx>
> has announced plans to launch a new camera featuring the sensor in the
> coming months. Nor is 50 megapixels going to remain on the cutting edge for
> long. Just this week, a few days after Kodak's announcement, another
> digital-imaging firm, DALSA <http://www.dalsa.com/>, based in Waterloo,
> Canada, announced that it has developed a 60-megapixel sensor.
>
>
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In reply to: Message from vick.ko at sympatico.ca (Vick Ko) ([Leica] 50 Meg Kodak sensor - maybe this is what's happening behind the doors at Solms:)