Ok, here's the results. A comparison of pictures:
http://imgur.com/a/8IQgb#0
Feathered, are you Australian? You're always posting at Aussie hours... I'm on to you.
EDIT: Realistically gamma should be constant but exposure should change (imagine a camera's shutter speed). At night the exposure should be .7 or .9 whereas at day time the exposure should be 0.05 or so.