Months ago I decided to start painting some areas of the house. And, I did just that. I moved furniture, pictures and curtains and I painted. When I had completed the work I put some of the things back and the rest have either gone or are waiting to go to new homes.
I was pleased with my efforts - indeed I still am pleased with them.
So imagine my surprise when it came to my attention that something I thought I had painted was still the original colour. How did I miss that? I thought I had done a thorough job but weeks after the painting paraphernalia had been put away I noticed a yellow piece of wood amongst all the newly painted white bits.
It literally came to light one morning. All that was necessary for me to see this oversight was the correct lighting and the right perception.
When I saw it I immediately realised what I had done; I knew that I had painted when it was getting late in the day, with a yellowish light overhead (I know, it all sounds obvious now!) and I therefore had the perfect set up to obtain a tinted vision that obscured what was directly in front of me. The piece of wood appeared to have been covered in brilliant white paint but it remained yellow all this time.
Now with the right conditions I could plainly see what had always been in front of me. If the sun had not been shining right then, or my eyes had been focused elsewhere then I never would have seen what I had so easily omitted.
Without the right conditions then my painting in the dark would have seemed fine.