all 8 comments

[–]magnora7 3 insightful - 1 fun3 insightful - 0 fun4 insightful - 1 fun -  (4 children)

Many birds can see magnetic polarization in their eyes.

My friend can even see the direction of polarization of light, like on LED screens and stuff, apparently there's a technique to it where it appears more yellow one way and more blue another way.

Here's an article about the technique: https://www.polarization.com/haidinger/haidinger.html

I've tried it and I can't get it to work, but one of my friends can reliably see it.

[–]useless_aether[S] 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (3 children)

i played with polarized foils and filters a bit, they are great to use in photography to filter out reflections from lights, on the water, to make the blue sky more saturated, even as a neutral density filter. i cant see it though, usually its just a moire.

[–]magnora7 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (2 children)

Yeah polarized filters are great for seeing reflective surfaces, because shallow reflections naturally polarize light in one direction. Pretty cool stuff

[–]Tom_Bombadil 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (1 child)

Polarized films can also be used to see areas of residual stress in clear plastics.

The stressed locations refract light at slightly differing angles, which allow the bent light to be filtered.

[–]magnora7 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (0 children)

Yeah that is a very cool effect! It also brings to mind the rainbow in a puddle of oil on the ground in the rain, which refracts a rainbow of colors, the color depending on the thickness of the oil film on the water at that exact spot, which changes what frequencies are refracted and reflected. Light is so cool

[–]Farseli 3 insightful - 1 fun3 insightful - 0 fun4 insightful - 1 fun -  (2 children)

Reminds me of TMS: https://www.mayoclinic.org/tests-procedures/transcranial-magnetic-stimulation/about/pac-20384625

It's not surprising that the brain is affected by magnetic fields since it uses ions to send electric signals around.

My question is if it is actually possible for anyone to use this. I know of blind people able to use echolocation, so is this something that could potentially be used but first requires other stimuli to be removed?

[–]useless_aether[S] 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (1 child)

an isolation tank? i would really like to tell north without a compass !

[–]magnora7 3 insightful - 2 fun3 insightful - 1 fun4 insightful - 2 fun -  (0 children)

I have read about people who embed a small bar magnet in their finger, and after some practice they can learn this ability. Like a compass. Not sure how well it really would work though lol