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CCD vs interpolated
What is the difference? If it is advertized a certain MP, I have always
assumed CCD is more accurate, but don't know what the difference is. Thanks |
#2
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Richard Bornstein wrote:
: What is the difference? If it is advertized a certain MP, I have always : assumed CCD is more accurate, but don't know what the difference is. : Thanks I may be wrong, but I think you are talking two different things here. A CCD is a device that captures light intensity levels at specific locations. Interpolated is not a device but a process. I believe it is generally a way to double the number of pixels of a photo file by compairing the output of two adjacent pixels (picture elements), which could be captured by a CCD element, and creating an interpreted pixel to go inbetween. So one side of your equasion is a device and the other is a process. Now as to which is best, IMHO, a direct measuring of the image pixels would seem to be more accurate than a computer process "imagining" a proportion of the image elements. Most of the time when I have seen "Interpolated" it has been in relation to a scanner. By only having half as many image sensors as the final image would require, the cost is reduced. Sometimes with film scanners, some form of interpolation may be present as the miniaturization of the optics can create a limit on the number and size of image elements sensed. Eventually the cost of increasing the number of sampled points vs the cost of that increase becomes prohibitive. Randy ========== Randy Berbaum Champaign, IL |
#3
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Richard Bornstein wrote:
: What is the difference? If it is advertized a certain MP, I have always : assumed CCD is more accurate, but don't know what the difference is. : Thanks I may be wrong, but I think you are talking two different things here. A CCD is a device that captures light intensity levels at specific locations. Interpolated is not a device but a process. I believe it is generally a way to double the number of pixels of a photo file by compairing the output of two adjacent pixels (picture elements), which could be captured by a CCD element, and creating an interpreted pixel to go inbetween. So one side of your equasion is a device and the other is a process. Now as to which is best, IMHO, a direct measuring of the image pixels would seem to be more accurate than a computer process "imagining" a proportion of the image elements. Most of the time when I have seen "Interpolated" it has been in relation to a scanner. By only having half as many image sensors as the final image would require, the cost is reduced. Sometimes with film scanners, some form of interpolation may be present as the miniaturization of the optics can create a limit on the number and size of image elements sensed. Eventually the cost of increasing the number of sampled points vs the cost of that increase becomes prohibitive. Randy ========== Randy Berbaum Champaign, IL |
#4
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In article ,
"Richard Bornstein" wrote: What is the difference? If it is advertized a certain MP, I have always assumed CCD is more accurate, but don't know what the difference is. Thanks Is this regarding Fuji's magic sensor shapes that defy physics and double the resolution? Look for "effective pixels" of the sensor. That's how many sensor points are actually in use. The lens quality matters a lot too because plenty of 8MP cameras are so blurry that they offer nothing more than their 4MP predecessors. |
#5
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In article ,
"Richard Bornstein" wrote: What is the difference? If it is advertized a certain MP, I have always assumed CCD is more accurate, but don't know what the difference is. Thanks Is this regarding Fuji's magic sensor shapes that defy physics and double the resolution? Look for "effective pixels" of the sensor. That's how many sensor points are actually in use. The lens quality matters a lot too because plenty of 8MP cameras are so blurry that they offer nothing more than their 4MP predecessors. |
#6
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Richard Bornstein wrote:
What is the difference? If it is advertized a certain MP, I have always assumed CCD is more accurate, but don't know what the difference is. Thanks Its the native resolution of the CCD that counts, interpolation just gives you big files - and you can do that yourself in photoshop if you really have to. Think of it in the same way as optical vs digital zoom. -- Rick Digital Printing www.intelligence-direct.com - 01270 215550 |
#7
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Richard Bornstein wrote:
What is the difference? If it is advertized a certain MP, I have always assumed CCD is more accurate, but don't know what the difference is. Thanks Its the native resolution of the CCD that counts, interpolation just gives you big files - and you can do that yourself in photoshop if you really have to. Think of it in the same way as optical vs digital zoom. -- Rick Digital Printing www.intelligence-direct.com - 01270 215550 |
#8
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Right now there are three kinds of sensors used in digital cameras.
CCD devices capture photons and read them out as a long string of buckets as in a bucket brigade. To get color, the individual cells are covered with red, green and blue (transmitting) filters. CMOS devices capture photons and read them out like SRAM, one storage location at a time. To get color, the individual cells are covered with red, green and blue (transmitting) filters. Foveon devices capture photons and read them out like SRAM, one storage location at a time. To get color, the individual cells have three different wells under the photon capture area. The lowest energy photons (red) are captured in the top layer, the mid-energy photons are captured in the middle layer, and the high energy photons are captured deeper in the 3rd layer. Each layer can be accessed individually. CCD and CMOS color sensors need to be processed by an algorithm that performs demoasicing (AKA interpolation). There are at least 22 different algorithms that perform this Bayer interpolation. Some are better than others on one kind of imaging, others better on other kinds of imaging. Almost everyone agrees that the pictures comming out of Bayer sensors are top notch. The Foveon sensors do not need this demosaicing processing, but they need a different color-discrimination process to obtain nice RGB colors. Most people can agree that well exposed Foveon images are top notch. Where the disagreement lies is with shadow level detail where many see that CCD and CMOS sensors have better shadow level detail due in part to the spectral sensitivity differences between the filter model of CCD/CMOS verusus the energy level discriminatioon of the Foveons. |
#9
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Right now there are three kinds of sensors used in digital cameras.
CCD devices capture photons and read them out as a long string of buckets as in a bucket brigade. To get color, the individual cells are covered with red, green and blue (transmitting) filters. CMOS devices capture photons and read them out like SRAM, one storage location at a time. To get color, the individual cells are covered with red, green and blue (transmitting) filters. Foveon devices capture photons and read them out like SRAM, one storage location at a time. To get color, the individual cells have three different wells under the photon capture area. The lowest energy photons (red) are captured in the top layer, the mid-energy photons are captured in the middle layer, and the high energy photons are captured deeper in the 3rd layer. Each layer can be accessed individually. CCD and CMOS color sensors need to be processed by an algorithm that performs demoasicing (AKA interpolation). There are at least 22 different algorithms that perform this Bayer interpolation. Some are better than others on one kind of imaging, others better on other kinds of imaging. Almost everyone agrees that the pictures comming out of Bayer sensors are top notch. The Foveon sensors do not need this demosaicing processing, but they need a different color-discrimination process to obtain nice RGB colors. Most people can agree that well exposed Foveon images are top notch. Where the disagreement lies is with shadow level detail where many see that CCD and CMOS sensors have better shadow level detail due in part to the spectral sensitivity differences between the filter model of CCD/CMOS verusus the energy level discriminatioon of the Foveons. |
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