Light experiment

[clarknight]

Try this.
Both eyes open.
Patch one eye with a black patch for 30 seconds, until the darkness causes the pupil to enlarge.
Notice the intensity of light and brightness of color of the visual field seen by the unpatched eye.
Now, remove the patch.
Quickly cover the other eye and notice the difference; increased intensity of light, color seen for a short time by the eye that was patched. This difference occurs due to the large pupil temporarily letting more light into this eye.
When the mind, eyes, eye muscles relax, the iris muscles relax, function correct, the pupil becomes larger when needed increasing clarity, color, brightness of the visual field.