"Now it turns out that sometimes by chance, if the sun is partially covered or surrounded by scuddy clouds or fog, then around each one of these sun images, you actually see the clouds going by.
"The reason the sun shows up so well is that the sun is so bright. But actually, each hole also lets through a complete image of whatever is on the other side, including the sky, the houses, the people. This led to an exhibit - Holes In A Wall.
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