Noise on Low iso with 7D

I agree, but with one small exception, and that is blue sky.  Especially when photographing flying birds against a blue sky, if I don't add enough exposure compensation when taking the shot, I do get a bit of noise in the sky with my 7D, even at ISO 400.  (Less than 400 is too insensitive for my 400 f/5.6L lens.) However, in the scheme of things, it's not something I ever worry about.  I've never noticed it in shadows.

FF