Posted on April 21, 2022 by WillemThursday/ do rainbows have seven colors? Here is my picture of tonight’s rainbow that was visible just before sunset, now at 8.08 pm. Rainbows are optical illusions: reflected sunlight that is scattered by suspended drops of moisture in the atmosphere. Moreover, the multicolored band with ‘seven’ colors is an artefact of human color vision. There is no banding in a black-and-white photo of a rainbow, only a smooth gradation of intensity to a maximum, then fading again towards the other side.– Paraphrased from the Wikipedia entry for Rainbow.