B8 radiometry?

Hi,

Is it logical that TOA reflectance for vegetated areas in B8 (842 nm) is almost always lower than those in B7 (783 nm) and B8A (865 nm)? I would expect only the latter. This happens in a majority of scenes that are not much affected by atmospheric effects, and, thus, where atmospheric correction is unlikely to make up for the difference (I can’t check because have not got sen2cor to do anything useful).

I was wondering whether this means it is better to leave B8 out of red-edge analysis. Also, NDVI’s derived from B8 and B8A will be significantly different.

Guido