Originally posted by Digitalis I'm not sold on the Ultraviolet hypothesis, the reason being is that borosilicate glass is pretty damn good at attenuating those high frequencies
I understand what you are saying, but I believe it is the near UV light that is in question, plenty of which makes its way to the sensor. As you know, it is that portion of the spectrum that is so problematic for landscape film photography.
Originally posted by Digitalis and also the existence of a UV/IR absorbtion layer in font of the sensor will also soak up residual UV light.
...and may be the cause of the problem.
I would have to do the experiment myself to see whether there is any truth to it, but the absence when UV is absent followed by presence when UV is present would seem to implicate UV.
As for intensity, I guess it would depend on the light.
Steve