In addition: does the change in the pupil size affect the way we perceive depth of field?
In: Biology
We do squint which is a natural reaction to bright light. The vision cells also work differently in bright light then in dim light. And of course our brain does normalize the sensory input from our eyes so we do not perceive brightness. But other then that there is no control of light intake into the eyes.
The size of the pupils does technically change the depth of field. However eyes are very fast at focusing and have a tiny angle of view so we do not even notice our depth of field. And any lack of both depth of field and view angle is compensated for by the brain and its memory. So the aperture of the pupils does not really matter that much.
The cells that absorb light get washed out and less sensitive with bright lights, and slowly more sensitive while in the dark. This is why your eyes hurt for a minute when walking outside on a bright day.
Yes they do. In fact the aperture of the pupils is a relatively small factor in how the eyes adjust to brightness.
The main mechanism is the conversion of the substance rhodopsin to the substances retinal and opsin (and then back to rhodopsin). Unlike the pupil size change, the chemical change can take a few minutes, which is why it takes a while for us to adjust after a sudden change from light to dark or dark to light.
It definitely affects depth of field. It’s more of a big deal for other animals, though. Perhaps you’ve seen the “TARGET ACQUIRED” look of really huge pupils on cats right before they pounce? That’s not so they have more light necessarily, it’s more so they have a narrower depth of field around the thing they’re about to pounce on so they can make an accurate leap.
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