Yesterday's amusement involved eye-brain colour confusion. Our front room downstairs has one very dark purple (aubergine) colour wall and three white walls - Or So We Thought. It being a month after the plaster was replaced, I painted the new plaster white - and soon discovered that the existing paintwork was significantly darker than the new white paint. We figured the colour was cream or "antique white", so I mixed up a small amount of cream paint with the yellow paint we'd bought for the kitchen. After applying that to the wall, we found it was still not dark enough. After some moments of confusion, Richard suggested we try the undiluted yellow paint - and we discovered even that is paler than the wall! We in fact have one purple wall and three pale gold walls!
It's just very very strange to spend three months thinking that you have a room that's basically white, and then discover that actually it's yellow. And it says a lot about the brain's ability to adjust colour balance - the fact that because the room is large and bright with one very dark wall, our brains had adjusted to assume that the other walls had to be white. Confusing. Then in further proof of this principle, I painted a tester called "Velvet Plum" onto the bottom of the dark purple wall, because it had looked almost the right colour in the shop. On our wall, it appeared a tasteful but fairly bright pink. I was surprised, but figured it might do to replace the pinky lilac in the spare room (I've been trying to avoid painting that room lilac after we did our upstairs front room in finest Sims lavender - much as I like purple I think an entire house of it could be too much) - but when I tried it there, it came out as a dark purple! Richard & I had an amused few minutes standing in the hallway with both walls in view, watching the same colour simultaneously appear as a bright pink and a dark purple. Weird.
So I feel the need to link again to the shades of grey optical illusion and associated explanation, because it is in fact relevant. For once.