I have noticed that the Night Vision traits do not really work, the only effect they all have is, and it happens to be the same for all of them, making you be able to kind of see in the dark but not as much as supposed:
I myself currently have Full Night Vision, and I supposedly should be able to see in the dark as if I was wearing NV goggles.
And yes, I have the trait activated and no, it’s not a thing about the tileset.
I just tested night vision in both outdoor and indoor settings.
There is a noticeable difference between the different traits. Night Vision is better than not, full night vision is the best. I see it functioning, at least for me, as it always has.
I’m not sure what your screenshot is intending to show, it’s too small a room and even basic nightvision would display what we see there. What do you feel you should be able to see, but can’t?
Nightvision shows tiles as if they’re dark, since they still are. Only actual light or a clairvoyance artifact will show them in full color. It doesn’t have any actual effect ingame though, although nightvision doesn’t let you craft in the dark.
Cataclysm Quick Tip #27 - Perception and Night Vision
Wearing goggles and whatnot also weakens your nightvision.
I have Full Night Vision, and from what I understood it should let me see as if I was wearing NV goggles. Currently it doesn’t matter whether I have it on or off, in the dark I always see like:
NV goggles apply a green tint to everything you see. Night Vision mutations just let you see more tiles in the dark. It appears to be working perfectly in every screenshot you’ve showed.
Base = 1 square
Perception / 3 = +x squares
NV1 = +2 squares
NV2 = +4 squares
NV3 = +6 squares
You lose 1 square of NV for every 10 points of eye encumbrance.
I very much appreciate that your name is techincal and you gave us the most technical answer.