# 90% occlusion = half-brightness // 99% occlusion = quarter-brightness // 99.9% occlusion = 1/8th brightness // Eclipses, Audio Power, and the mathematics of Human Perception

## Mathematics of Human Perception

Listening to WTOP FM news in Washington, DC today, “eclipse day 2024”, it was hammered home to me how little even smart people understand the mathematics of human perception.

DC experienced an 88% to 91% occlusion, depending on exact location.  News casters and commentators kept harping on how dark it would become during near-totality / partial-eclipse.  Afterwards, they seemed surprised that the sunlight only seemed to dim down to ‘about half as bright’ as prior (afterwards, the chemtrails that had been sprayed early today had milked-out the sky into the familiar haze).

Human perceptions operate logarithmically.  So 90% “dimmer” only equates to about “half as bright”.  It works the same way with sound.  And with taste.  And with vibration.  And with color.  Our perceptions are largely, generally logarithmic.  That means it takes about a ten-to-one (or one-to-ten) change before we notice and can say there is a perceptible difference without doubt (for nearly 98% of humans).  Audio power has to increase ten times before it sounds twice as loud (or decrease ten-times to seem half as loud).  99% eclipse occlusion, therefore, would result in the remaining sunlight seeming only “about one-fourth as bright” .  99.9% occlusion (dimmer) would be about one-eighth as bright.  99.99% occlusion (dimmer) would be about 1/20th (really 1/16th), which would seem like ‘the nickel on the dollar’ and probably be called “about 90%” by most observers.