Turning Blue Optical Illusion Poster

There exist no blue colour in this image whatsoever. For a better view the magnifier (View a larger image) should be used. Now focusing strictly on the black star in the centre of the image, counting to 50 or more (just as an example) will make slowly the four circles diminish in the field of vision. At this moment, moving slowly the eyes in all directions will create a dance of blue crescents inside the circles, which finally turn bright light blue. The longer the observation, the deeper the light blue colour. (Please note: Images of similar colours in this category "Creating Illusory Colours", should not be watched one after the other, otherwise the to-be-created colour will be present from the start. It is better to wait a certain period of time - like 15 minutes - before viewing another image with the same colours.)