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> you could reduce that by making the surface locally rough or having random geometric segments That actually makes the problem much worse. Normally with a fe

> you could reduce that by making the surface locally rough or having random geometric segments That actually makes the problem much worse. Normally with a few flat reflective surfaces around, you'll catch occasional reflections of sunlight and flinch away from them. But with a very reflective rough surface, you catch reflections of sunlight every direction you look and it will burn your eyes. This is how "snow blindness" works. Fresh white snow is very reflective and very rough, on a bright day with fresh snow, you catch sunlight reflections every direction you look and if you don't limit your exposure, you can get painful UV burns on your eyeballs. Sunglasses or traditional snow goggles become essential if you're outside for long in these sort of conditions: https://en.wikipedia.org/wiki/Snow_goggles https://en.wikipedia.org/wiki/Snow_goggles It can also happen when you're on the water on a bright day, depending on the state of the waves. At somewhere around sea state 1 or 2, you start catching sunlight reflections off waves every direction you look and if you don't have sunglasses you'll be in for a shitty time. When it happened to me, it felt like having glass powder trapped under my eyelids.

college_physics 4y ago
> That actually makes the problem much worse the more directed the light source the more damaging for retinas (all other things being equal). that is why you have prohibitions on powerful laser pointers. what you are describing is the effect where diffuse reflections can integrate over time (since the impact is not immediately felt) and cause damage this way
- slackdog 4y ago
  > the more directed the light source the more damaging for retinas (all other things being equal). Yes certainly, but in the real world the human blink reflex means that all other things aren't equal. If you walk past a shiny glass building, you might catch a reflection of sunlight but only for a brief instant. Turn another direction and you'll see another shiny building, but you probably won't get a sunlight reflection off that shiny building because the angles are different and the sunlight is being reflected somewhere else. You can walk around a mirrored city all day and your eyes will be fine. But when you're surrounded by diffuse reflectors, now can't turn away from that reflected light. A city of pure white reflective buildings would be likely be quite painful on a bright day.
aksss 4y ago
Black Sabbath has entered the conversation

college_physics 4y ago

> That actually makes the problem much worse the more directed the light source the more damaging for retinas (all other things being equal). that is why you have prohibitions on powerful laser pointers. what you are describing is the effect where diffuse reflections can integrate over time (since the impact is not immediately felt) and cause damage this way

slackdog 4y ago
> the more directed the light source the more damaging for retinas (all other things being equal). Yes certainly, but in the real world the human blink reflex means that all other things aren't equal. If you walk past a shiny glass building, you might catch a reflection of sunlight but only for a brief instant. Turn another direction and you'll see another shiny building, but you probably won't get a sunlight reflection off that shiny building because the angles are different and the sunlight is being reflected somewhere else. You can walk around a mirrored city all day and your eyes will be fine. But when you're surrounded by diffuse reflectors, now can't turn away from that reflected light. A city of pure white reflective buildings would be likely be quite painful on a bright day.

aksss 4y ago

Black Sabbath has entered the conversation