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It is just because it is midsummer - and the light is not useful all the time. It is just like one long prolonged sunset. We are about the same l latitude as Scotland and I guess we are lying directly at the point where the phenomenon accelerates. The days are longer (and shorter in the winter) in the Northern part of Denmark which is about the same as the Scotch highland.

And the flipside: Winter. When I painted I only had a few hours to do the colour choices a the middle of the day. There is not enough light - so the rest of the day I worked with light darkness problems...