I use a very bright spot light and only hunt in the dark! Just kidding!
When I hunt a bed area, I try to be there really early and most times it is very dark, so I use a flash light. I'm hoping that I beat them there while they're still out feeding, but that's not always the case. I don't think it matters a whole lot anyway. After a while I've found that they seem to go back to their routine. At least where I hunt.
When I hunt a feeding area I try to get there early as well, but it is usually in the early afternoon when it's light. When it gets dark, I try to be quiet and not get busted climbing down from my stand, but just walk as normal leaving. I've found over the years that if deer get used to seeing you leaving the area and you're not too close, they aren't so bothered by your presence. After all, they know where you are, and you're headed away from them.