I found yesterday’s rainbow picture to be so delicious that it had to be savoured alone: it was the nicest shot I have managed of a semicircular bow replete with its reflection in the calm waters of the Lake.
Yet, during the half-hour I watched the rainbow, features shifted as the shower moved along the Lake and the lighting changed. There was much to see.
The colours of the rainbow blend continuously one into another. The crayon-box claim that there are seven colours in the bow is silly: the standard mnemonic, Roy G. Biv (red, orange, yellow, green, indigo, violet) merely gives the order of colours that may or may not be seen, but which are certainly not discrete. Other striking features seen here are that red is on the outside of the curve (not on the inside as much commercial art suggests), and it is brighter inside the bow than outside.

There is a much to discover in the next scene: bright central disk, anticrepuscular rays forming radii to the bow, a larger secondary bow with red on the inside, faint supernumerary bows on the inside of the primary bow, and colours improving as the bow becomes nearly vertical. A particular feature might not be evident in every rainbow, but as one watches the bow evolve, each is worth descrying. The fact that these characteristics are well understood only enhances the grandeur of the event.
