DSPographer
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Color accuracy
Color accuracy
In the absence of errors introduced by compression, color accuracy of *linear* raw data improves with exposure as long as there is no clipping. This is because the signal to noise ratio of each photosite improves with the amount of signal measured. The accuracy of the ratio of the color components therefore also improves as the signal level increases. After a nonlinear curve has been applied to the raw data this may no longer be true but as long as the color correcting is done with sufficient precision using the raw data the rule that increased exposure means increased color accuracy will be true. Of course a properly color balanced light source will help in maximizing the exposure of all color components for lowest color noise. Note that the level of a distant part of the image being gray or black will not affect the color accuracy as long as light from that distant part of the image doesn't leak to where we are measuring.
Color accuracy
In the absence of errors introduced by compression, color accuracy of *linear* raw data improves with exposure as long as there is no clipping. This is because the signal to noise ratio of each photosite improves with the amount of signal measured. The accuracy of the ratio of the color components therefore also improves as the signal level increases. After a nonlinear curve has been applied to the raw data this may no longer be true but as long as the color correcting is done with sufficient precision using the raw data the rule that increased exposure means increased color accuracy will be true. Of course a properly color balanced light source will help in maximizing the exposure of all color components for lowest color noise. Note that the level of a distant part of the image being gray or black will not affect the color accuracy as long as light from that distant part of the image doesn't leak to where we are measuring.