I have been looking at this tutorial from Astostuff on taking off the hot mirror on a D70, but cannot figure out from the page where the color mosaic filter is located.
Is it possible to remove the color mosaic filter off the sensor? Does converting the camera to IR involve removing the filter? Will I achieve any significant gains by removing the color mosaic filter? Does the color filter not absorb IR photons?
Answer
It's possible to remove the CFA (colour filter array) but extremely difficult. There is at least one company that will do it (Maxmax as asalamon74 states). Doing this is entirely unneccesary for IR conversion, in fact one of the things I like about IR photography is playing with the faint colours that result, which requires the CFA.
As to why you'd want to remove it... sensitivity. Each of the colour filters filters out approximately two thirds of incoming light. Removing them would give you a greyscale camera that's 1.6 stops more sensitive, so where you'd have to use ISO1600 normally with this camera you could shoot at ISO500
Also you wouldn't have to demosaic the resultant images so you'd get an increase in sharpness similar to what you get with a Sigma Foveon camera.
If you do a deep IR conversion (880nm or shorter) then you lose colour information anyway so you have nothing to lose by removing the CFA.
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