Comment 5 for bug 1411958

OK, I also see it now on the x64 RC4. There is no flicker on MinGW/win32. A real showstopper! :-(

I think there is some numerical extinction happening here, but I dont's see how at the moment if we use doubles only, and why this involves lunar brightness, exclusively. Esp I don't see where to avoid it. There is a division with an end result very close to 1, if some user of this result subtracts 1 and uses the result, strange consequences may be expected. But where in the code around lunar brighness is that?

The previous solution for refraction was numerically wrong but does not cause flicker for the moon on x64. Shall we, if necessary, postpone really fixing it towards 0.14 or further (if at all possible?)