Optical Illusion

After a cool start the day warmed up a little. In the afternoon a storm blow in, dropped some rain and then disappeared just as quick. I heard some thunder. Really strange one!

I just went out into the garden to take some shots when the storm appeared. It got dark really quickly. Did manage to get this shot. When I look at it sometimes it is inverted.. I look away and it comes back to was it was again. Sure is a trick to the eye.