Originally Posted by Merlin66
Removing the colour balancing filter improves the red response, from 30% to around 85% but leaves the front anti-alias/ dust filter as a UV-IR cut-off (400nm-700nm)
If the front filter is also removed (Full spectrum) then the camera will "see" from 380nm to well out into the NIR - no futher increase to the Ha response.
That must be how they plan to do the Nikon D800E with no low pass filter.
Since the dust shaker models have come out its 2 filters. So one is the UV/IR and one is the AA filter.
I also notice there is a company MaxMax who modify DSLRs and one option is for high definition filter. It must be an optical flat glass replacement for the AA filter to effectively create a D800E out of any camera. The downside would be moire patterns on some objects.