This is easier to do in low light, when only your rods (sensitive black-and-white cells) are active and your cones (less sensitive color-detecting cells) are basically "off" because there's not enough light.
What interesting about adaptation is that it makes edges of things stand out. If your eye moves a bit, but a cell is still looking at something that's the same color (or same brightness, if it's a rod), then adaptation will still happen.
Cones in your eye are much denser toward the center (fovea), so if you're looking at something dim like a star, try "aiming" the center of your eye a little to one side. That way the sensitive rods are denser in your But if you're looking for tiny variations in color, use the center of your eye.
Also, if you're looking for a something static, it helps to blink. This triggers a neurological "flush" in your visual system and helps to reset the adaptation.
But if you're looking for something moving, try keeping your eyes fixed on one point. Adaptation happens gradually, so everything holding still will immediately fade slightly and the moving object will stand out.
I wonder why the eyes had to develop a method to defeat adaptation from the brain. A quick google search yielded no answers, but if I had to guess, neural adaptation developed first in simple nervous systems because it helped organisms react to changes, such as a changing water current when a predator was nearby. As complex vision developed, it became advantageous for organisms to not go blind momentarily for some reason, perhaps because changes in the environment can be better predicted with constant sight. Organisms that didn't go blind had an advantage, and the method for them not to go blind was for their eyes to jiggle imperceptibly but just enough for the brain not to adapt. That would be my guess anyway. Detecting only changes works better for "simpler" senses like touch, but sight works better when it's not arbitrarily turned off by the brain.
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[ 3.1 ms ] story [ 25.4 ms ] threadYou having a bubble bath, BBC? This is really taking the Michael.
Non sequitur.
What interesting about adaptation is that it makes edges of things stand out. If your eye moves a bit, but a cell is still looking at something that's the same color (or same brightness, if it's a rod), then adaptation will still happen.
Cones in your eye are much denser toward the center (fovea), so if you're looking at something dim like a star, try "aiming" the center of your eye a little to one side. That way the sensitive rods are denser in your But if you're looking for tiny variations in color, use the center of your eye.
Also, if you're looking for a something static, it helps to blink. This triggers a neurological "flush" in your visual system and helps to reset the adaptation.
But if you're looking for something moving, try keeping your eyes fixed on one point. Adaptation happens gradually, so everything holding still will immediately fade slightly and the moving object will stand out.