flavio Posted May 7, 2007 Share #1 Â Posted May 7, 2007 Advertisement (gone after registration) Hello, I have a basic question: does DNG is a format who altere, influence in some way the original data taken by the sensor or keep it all with no change? Â Thanks indeed! Link to post Share on other sites More sharing options...
Advertisement Posted May 7, 2007 Posted May 7, 2007 Hi flavio, Take a look here DNG Format. I'm sure you'll find what you were looking for!
joachimeh Posted May 7, 2007 Share #2 Â Posted May 7, 2007 The pure data read from the sensor are the red, blue, green values for the amount of photons collected in the Beyer-mosaic. These values are "preprocessed" in the camera to deliver meaningful RGB values for output into DNG, RAW, JPG formats. That preprocessing algorithm can be considered to determine the character of the camera. _____________________________________________ Regards, Joachim Link to post Share on other sites More sharing options...
sandymc Posted May 7, 2007 Share #3 Â Posted May 7, 2007 DNG as a format can support either totally raw data, or data that has been processed to a greater or lesser extent. Â The specific implementation of DNG in the M8 is "semi-processed" - the raw sensor data has been processed to adjust for black level, to compensate for vignetting, been compressed, etc. It still however in the form of Bayer matrix data, so RGBG, not RGB. Â Sandy Link to post Share on other sites More sharing options...
mjh Posted May 7, 2007 Share #4 Â Posted May 7, 2007 I have a basic question: does DNG is a format who altere, influence in some way the original data taken by the sensor or keep it all with no change? All cameras apply some processing to the raw data. Specifically, the M8 will compensate for the red vignetting caused by an IR/UV filter, provided the lens is coded and the firmware can predict the amount of vignetting to correct for. Also, the DNG files produced by the M8 (but not the DMR) contain compressed data. On the other hand, DNG files capture just one colour channel per pixel; the demosaicing (i.e. the interpolation of the two missing components of the RGB triple) and the conversion from the device-dependent colour space of the sensor to a device-independent colour space such as Adobe RGB or sRGB are left to the raw converter. Link to post Share on other sites More sharing options...
flavio Posted May 14, 2007 Author Share #5 Â Posted May 14, 2007 Joachim, Sandy and Michael, thank you very much for your explanation. I understand that, beyond the camera you use, DNG introduce an influence in the sensor view. The kind of influence may depends on the camera firmware. Maybe the same can be said for the RAW format. Probably depending from the firmware we can say we don't have any totally free from influences way to see what and how a sensor sees the subject. Correct? Â Thanks again. Link to post Share on other sites More sharing options...
sandymc Posted May 14, 2007 Share #6  Posted May 14, 2007 Flavio,  I can't speak for all Raw formats, but certainly Nikon and Canon raw formats are as "processed" as Leica DNGs  Regards,  Sandy Link to post Share on other sites More sharing options...
flavio Posted May 14, 2007 Author Share #7 Â Posted May 14, 2007 Advertisement (gone after registration) Sandy, thank you! Link to post Share on other sites More sharing options...
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