Bill, yellow, amber, and brown tints increase contrast. The lighter tints help vision on an overcast day when dark glasses would be too much. I find a yellow tint helps me more when I'm driving at night (or in the rain) than an anti-reflective coating.

Tom uses yellow goggles inside to cut the glare caused by his type of blindness. (But the orange ones that protect the eyes from a laser are even better.)

Linn