Your eyes a much larger sensor area than the opening, they do the opposite of concentrating light in a small area.

A point source in the visual field will create a point image on the retina. The "sensor area" you're referring is what's necessary to capture the entire visual field simultaneously.

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Retric 2 days ago | parent [-]

I disagree that it’s a point source at distances of peak concern.

Also, it’s something of a nitpick but physically point sources still end up as a circle.

	▲	AlotOfReading 2 days ago \| parent [-]
		That's fair, strictly speaking, but I'm not sure there's a meaningful difference to be made. Wasn't sure what level of knowledge you were coming from re: PSFs, so I was keeping it basic.