Peripheral Vission

[I_Hate_Infinity]

Right AB'ers I've got a real *** here.

I've noticed my whole life that when I look up at the stars in the night sky I often can't even see a star that's faint until I look at one that's near and then the other one pops into light out of me peripheral vision... So straight up question;

Why does peripheral light reach my retina instead of direct visual alignment with the light source??

I'm aware of the blind spot in our vision due to the optical nerve blocking retinal receptors in our eyes but I only know it affecting peripheral vision, which is clearly not what is happening with this phenomenon....

Confused. Any eye-deas ;) ?

IHI

[mibn2cweus]

The area of the retina upon which our field of view is centred is cone rich for colour vision. This area, the fovea, is surrounded by the much more dim light sensitive rods.

https://en.wikipedia.org/wiki/Averted_vision

[woofgang]

Its a well known phenomenon at sea (or used to be). When on watch at night looking for other ships, distant lights are seem more clearly if you don't focus on them. Its hard at first because people grow up not working that way but once you learn to do it, its with you for life.

[Clanad]

Not only is peripheral vision superior for night vision it is also better able to detect and recognize movement (which benefited our hunter ancestors) than direct vision.

[beso]

The problem would be enhanced with blue stars because the blue cones are outside the fovea.

Blue light also tends to go out of focus due to its refraction being greater.

[Hypognosis]

@beso

That was news to me, despite doing a physiology unit at uni, so I had to look it up. Sure enough, this confirms it.

http://hyperphysics.phy-astr.gsu.edu/hbase/vision/rodcone.html

[Zacs-Master]

Hence why people like blue LED Christmas lights as they look like stars.