I put some Sherwin Williams Repose Gray on two walls... and it looks blue to me. First impression was 'oh, baby blue'. Before I put it on the wall, I put it on some poster board and it looked how I expected. I put some more on a new piece of poster board, still looks ok. However, on the walls it's blue. It looks blue regardless of the light conditions and the time of day. Is there something wrong with my walls? The paint has primer in it.