About: all sorts of spectral colored optical phenomena, such as: the primary and secondary rainbows, the circumzenithal and circumhorizontal arcs, the glory (the system of rainbow-like rings around the point at 180° from the sun), the corona (around the sun), Bishop's ring (a very vague and broad copper-colored ring around the sun after a volcanic explosion, created by sunlit ash particles in the stratosphere, with bright lightbluish inner region very near the sun), Iridescent clouds, Mother-of-pearl clouds, etc... would look much more colored if the lightsource was pointlike (or starlike) instead of disc shaped, like the sun. Could it be that the spectrum of, for example, the Primary Rainbow would look much more R.G.B.-like (Red.Green.Blue-like) instead of the well-known Red-Orange-Yellow-Yellowish Green-Green-Cyan blue-Indigo Blue? (thus: the TRUE spectrum, without the overlapping colors orange, yellow, yellowish green, and Cyan blue).
Most digital simulations of the Primary and Secondary rainbows show the appearances of these optical phenomena in all possible diameters of the sphere-shaped raindrops and tiny mist-droplets, all created by the disc shaped sun. But... they don't show them in the light of a pointlike lightsource, such as: a very bright supernova. Imagine... our sun as a very bright pointlike lightsource (the same magnitude as the true sun). Not only the spectral colored optical phenomena would look different, also the shadows cast by sharp edged clouds! There would always be odd looking shadowbands moving across the ground and on the walls of buildings and houses. A list of all such enhanced optical phenomena is pretty long! I wonder if I'm the first one who has this sort of thoughts in the mind... (it's not something to talk about on the daily workfloor, or during break, so... I do it here in Astrobin).
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