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Camera Talk / Re: Nikon, why no "Monochrome" digital camera?
« Last post by Les Olson on Today at 08:17:52 »The first thing to remember is that B&W film is not equally sensitive to all wavelengths of light, and the wavelength sensitivity of films varies quite a lot. There is a convenient graphic showing a bunch of film spectral sensitivities at www.linabessonova.photography/spectral-sensitivity showing how much they vary. The amount of silver in an area of film is not just a measure of light intensity, and a B&W film image is also a record of the colour of the light.
The same is true of digital sensors. Silicon is not equally sensitive to all wavelengths, so the voltage output of a monochrome photosite is not just a measure of light intensity - it also varies with the colour of the light (micromagnet.fsu.edu/primer/digitalimaging/digitalimagingdetectors.html). In a monochrome sensor you don't know how colour and brightness combine to determine a photosite's output, but if you have the Bayer filters you do know the colour of the light each photosite saw so you can adjust for the spectral response and reconstruct the luminance information more accurately.
You do get a small increase in resolution by getting rid of the Bayer mosaic. That may have been worthwhile when we had 6MP sensors, but until someone invents a higher resolution printer it doesn't make any difference with modern sensors.
The same is true of digital sensors. Silicon is not equally sensitive to all wavelengths, so the voltage output of a monochrome photosite is not just a measure of light intensity - it also varies with the colour of the light (micromagnet.fsu.edu/primer/digitalimaging/digitalimagingdetectors.html). In a monochrome sensor you don't know how colour and brightness combine to determine a photosite's output, but if you have the Bayer filters you do know the colour of the light each photosite saw so you can adjust for the spectral response and reconstruct the luminance information more accurately.
You do get a small increase in resolution by getting rid of the Bayer mosaic. That may have been worthwhile when we had 6MP sensors, but until someone invents a higher resolution printer it doesn't make any difference with modern sensors.

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