I've noticed on some away exploration missions, some planets seem to have tons of dense fog or whatever that darkens everything. Doing those are annoying. I've seen it on both fed & klink side, though.
Ok I just started the Breen series on my KDF , the first planet Iand on (Defera) I can see every detail on my guys. I think they made the ground missions KDF side dull and dark to give it a "evil" feel.