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#171
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Sigma Digital SLR Cameras.
If you are the real GP welcome
If not, sod off troll Please forgive me if it really is you George but I believe your identity has been hijacked on several occasions This may be one too Arts "Georgette Preddy" wrote in message om... Andy Fraser wrote in message ... In rec.photo.digital, Georgette Preddy uttered these immortal words: foveon is 2250 x 1500 pixels. that is only 3 mp. A 2230 x 1500 image requires exactly 2250 x 1500 x 3 sensors. Obviously. Don't you realize there are 3 color channels? I'm hoping someone can help me understand this better. I went to the Sigma website and looked at the specs of the SD10 and sure enough they say this camera produces images that are 2268 x 1512 x 3 layers. Here's where I get confused, please bare with me. If I take a picture taken with my Kodak 5MP camera (I'm not about to attempt to compare these 2 cameras BTW) and save it as a bitmap I get a file that's 14,953,734 bytes in size. That's what I'd expect given the resolution of 2580 x 1932 x 3 bytes per pixel, 1 each for the red, green and blue values of each pixel. The fact that that picture was arrived at by applying an algorithm to the data from the Bayer mosaic filter CCD jobbie is irrelevant to what I'm getting at. AIUI my camera produces a photograph with nearly 5 million true colour pixels in it while the Foveon X3 method used by the SD10 produces a 3.4MP true colour image. If you drew a 5M pixel image by hand with Microsoft Paint, then saved it as a TIF it would be the same size too. That doesn't make it an optical photograph. All that matters is the optical quality of the optical data, the number of pixels are irrelevant, any image can be upscaled to consume any number of pixels. A 6MP Bayer has 6M monochrome sensors, a 3.4MP (output is 13.72MP) Foveon has 3.4M full color sensors. It would take a 13.72MP Bayer to equaly the quality of Foveon data, if such an enormous sensor existed. I suggest reading Phil Askey on the subject... "The Foveon X3 sensor captures full color for each pixel location and thus requires no demosaic processing, a single individual pixel has its own distinct color without influence from neighbouring pixels. This leads me to the term 'Single Pixel Resolution', the X3 sensor's striking ability to capture image detail down to a single pixel level, such as a wire which in the image is just one pixel across. You can of course produce similar results from a Bayer sensor camera by downsampling an image by 50% [meaning 25% of the original image area], this is (approximately) the same as combining two green, one red and one blue pixel together. To achieve this and be left with an image of the same size as the SD10 you would need 4536 x 3024 (13.7 megapixel) input image." |
#172
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Sigma Digital SLR Cameras.
If you are the real GP welcome
If not, sod off troll Please forgive me if it really is you George but I believe your identity has been hijacked on several occasions This may be one too Arts "Georgette Preddy" wrote in message om... Andy Fraser wrote in message ... In rec.photo.digital, Georgette Preddy uttered these immortal words: foveon is 2250 x 1500 pixels. that is only 3 mp. A 2230 x 1500 image requires exactly 2250 x 1500 x 3 sensors. Obviously. Don't you realize there are 3 color channels? I'm hoping someone can help me understand this better. I went to the Sigma website and looked at the specs of the SD10 and sure enough they say this camera produces images that are 2268 x 1512 x 3 layers. Here's where I get confused, please bare with me. If I take a picture taken with my Kodak 5MP camera (I'm not about to attempt to compare these 2 cameras BTW) and save it as a bitmap I get a file that's 14,953,734 bytes in size. That's what I'd expect given the resolution of 2580 x 1932 x 3 bytes per pixel, 1 each for the red, green and blue values of each pixel. The fact that that picture was arrived at by applying an algorithm to the data from the Bayer mosaic filter CCD jobbie is irrelevant to what I'm getting at. AIUI my camera produces a photograph with nearly 5 million true colour pixels in it while the Foveon X3 method used by the SD10 produces a 3.4MP true colour image. If you drew a 5M pixel image by hand with Microsoft Paint, then saved it as a TIF it would be the same size too. That doesn't make it an optical photograph. All that matters is the optical quality of the optical data, the number of pixels are irrelevant, any image can be upscaled to consume any number of pixels. A 6MP Bayer has 6M monochrome sensors, a 3.4MP (output is 13.72MP) Foveon has 3.4M full color sensors. It would take a 13.72MP Bayer to equaly the quality of Foveon data, if such an enormous sensor existed. I suggest reading Phil Askey on the subject... "The Foveon X3 sensor captures full color for each pixel location and thus requires no demosaic processing, a single individual pixel has its own distinct color without influence from neighbouring pixels. This leads me to the term 'Single Pixel Resolution', the X3 sensor's striking ability to capture image detail down to a single pixel level, such as a wire which in the image is just one pixel across. You can of course produce similar results from a Bayer sensor camera by downsampling an image by 50% [meaning 25% of the original image area], this is (approximately) the same as combining two green, one red and one blue pixel together. To achieve this and be left with an image of the same size as the SD10 you would need 4536 x 3024 (13.7 megapixel) input image." |
#173
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Sigma Digital SLR Cameras.
If you are the real GP welcome
If not, sod off troll Please forgive me if it really is you George but I believe your identity has been hijacked on several occasions This may be one too Arts "Georgette Preddy" wrote in message om... Andy Fraser wrote in message ... In rec.photo.digital, Georgette Preddy uttered these immortal words: foveon is 2250 x 1500 pixels. that is only 3 mp. A 2230 x 1500 image requires exactly 2250 x 1500 x 3 sensors. Obviously. Don't you realize there are 3 color channels? I'm hoping someone can help me understand this better. I went to the Sigma website and looked at the specs of the SD10 and sure enough they say this camera produces images that are 2268 x 1512 x 3 layers. Here's where I get confused, please bare with me. If I take a picture taken with my Kodak 5MP camera (I'm not about to attempt to compare these 2 cameras BTW) and save it as a bitmap I get a file that's 14,953,734 bytes in size. That's what I'd expect given the resolution of 2580 x 1932 x 3 bytes per pixel, 1 each for the red, green and blue values of each pixel. The fact that that picture was arrived at by applying an algorithm to the data from the Bayer mosaic filter CCD jobbie is irrelevant to what I'm getting at. AIUI my camera produces a photograph with nearly 5 million true colour pixels in it while the Foveon X3 method used by the SD10 produces a 3.4MP true colour image. If you drew a 5M pixel image by hand with Microsoft Paint, then saved it as a TIF it would be the same size too. That doesn't make it an optical photograph. All that matters is the optical quality of the optical data, the number of pixels are irrelevant, any image can be upscaled to consume any number of pixels. A 6MP Bayer has 6M monochrome sensors, a 3.4MP (output is 13.72MP) Foveon has 3.4M full color sensors. It would take a 13.72MP Bayer to equaly the quality of Foveon data, if such an enormous sensor existed. I suggest reading Phil Askey on the subject... "The Foveon X3 sensor captures full color for each pixel location and thus requires no demosaic processing, a single individual pixel has its own distinct color without influence from neighbouring pixels. This leads me to the term 'Single Pixel Resolution', the X3 sensor's striking ability to capture image detail down to a single pixel level, such as a wire which in the image is just one pixel across. You can of course produce similar results from a Bayer sensor camera by downsampling an image by 50% [meaning 25% of the original image area], this is (approximately) the same as combining two green, one red and one blue pixel together. To achieve this and be left with an image of the same size as the SD10 you would need 4536 x 3024 (13.7 megapixel) input image." |
#174
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Sigma Digital SLR Cameras.
"Bart van der Wolf" wrote in message ...
"Georgette Preddy" wrote in message om... SNIP A 6MP Bayer has 6M monochrome sensors, a 3.4MP (output is 13.72MP) Foveon has 3.4M full color sensors. Nonsense, as usual. Sensors are not monochrome, nor are they full color. All Bayer MP ratings are strictly monochrome. Color is digitally interpolated after the shutter closes at an expense of -75% of the monochrome resolution. When a Bayer DSLR maker says 6MP, they mean 6M monochrome sensors, not full color. That is why you'll never see a color resolution test image used by on a site that is sponsored with big money from Bayer camera manufactures, like dpreview.com and imaging-resource.com. |
#175
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Sigma Digital SLR Cameras.
"Bart van der Wolf" wrote in message ...
"Georgette Preddy" wrote in message om... SNIP A 6MP Bayer has 6M monochrome sensors, a 3.4MP (output is 13.72MP) Foveon has 3.4M full color sensors. Nonsense, as usual. Sensors are not monochrome, nor are they full color. All Bayer MP ratings are strictly monochrome. Color is digitally interpolated after the shutter closes at an expense of -75% of the monochrome resolution. When a Bayer DSLR maker says 6MP, they mean 6M monochrome sensors, not full color. That is why you'll never see a color resolution test image used by on a site that is sponsored with big money from Bayer camera manufactures, like dpreview.com and imaging-resource.com. |
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