I'm red-green colour blind but have difficulty in describing colours in general (I see them and know what they are but sometimes (and especially if they're under a coloured light) I can't specifically say what colour a wall is, for example).
This is quite interesting as I can't really see second-by-second changes; at most I can see small jumps (not the radically large ones) you get every few seconds.
I'm not color blind, yet that is what I see, too. Makes me wonder about the brain's color-processing. My guess is small variations are ignored by the brain because slightly changing light conditions can cause all colors to vary slightly over time. Your brain filters them out so you can only tell when something really is changing.
This is quite interesting as I can't really see second-by-second changes; at most I can see small jumps (not the radically large ones) you get every few seconds.