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light intensity does that try this: take a picture, same object, no flash, ... one under normal bright sun and another in a room under normal bright lighting.
by dingleberry 8y ago
light intensity does that
try this:
take a picture, same object, no flash, ... one under normal bright sun and another in a room under normal bright lighting. which one is sharper?
set phone brightness to lowest, another on highest. try to read something and measure your arm's length. adjust brightness so you can still focus at farthest arm's length as comfort dictates. don't save on power juice. your eyes are more important.
drive outside and then go to underground parking lot. you'll notice it's harder to look.
use your normal glasses in a normal lighting room. go outside and swith to lower power (say your previous glasses). notice the difference.
the problem was i used the same power glasses all the time, out of habit. the very same glasses for reading far (chalkboards) and for reading books. it's somewhat not practical to switch glasses every time you copy something from board and write to your notes. using lower powered glasses and move my seat to the front mitigate this problem.
tldr; try to get maximum amount of light to your eyes as comfort dictates. if you really have to use glasses, choose the one with lower power that's sufficient for your need. practice to never use glasses for most tasks (adjust brightness on smartphone). you'll be surprised on what ur eyes can do without glasses.
- walterbell 8y agoIf glasses are an exoskeleton, use the minimum strength for: - phone (30 cm) - computer (60 cm) - board/driving (600+ cm) Now that you can buy good quality glasses online for less than $50 from the same Essilor labs that supply local stores, it is practical to wear situation-specific pairs, especially for computer work. More info: https://gettingstronger.org/2016/03/faq-for-vision-improvement-by-hormetism/ https://gettingstronger.org/2016/03/faq-for-vision-improveme...
- hetman 8y agoMore specifically it's the bright light triggering the iris to close that improves the focus. As the aperture narrows (iris closes) the incoming rays become more collimated (less scattered) and so the image falling on your cornea appears sharper even if your eye's lens is not able to focus it correctly. At it's extreme this effect allows the pinhole camera to work without using any lenses at all to focus the image. The thing is though, while using lower powered glasses might help you train the muscles around your eyes' lenses to be stronger, mitigating the myopia slightly, the root problem still remains: your eyeball is the wrong shape and there's only so much your eyes' lenses can do to make up for that.
- dingleberry 8y agonot really... seeing things under sun is not equal to squirting ur eyes to focus the incoming rays it's just that much light coming, the intensity of light to be exact. that's why camera, given the same setup, gives sharper image under bright sun light I never get as tired playing outside as compared to squirting my eyes all the time just to focus in a room. sun light is just that intense, rooms lightings are much less intense.
- hetman 8y agoCameras only give a sharper picture in bright light because this allows you to reduce the aperture size. The image is not sharper if you increase the shutter speed instead of reducing the aperture. This is basic physics. Bright light is not magical. Squinting your eyes is a very poor approximation to what your irises are doing. The light collimation is not reduced uniformly in every axis and your eyelashes partially obscure the light.