Why can a lace curtain be seen through by day from inside but not from outside?

1. 45

   Myn Is Meposted 12 years ago

   Why can a lace curtain be seen through by day from inside but not from outside?
   
   

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2. 59

   Viviannieposted 12 years ago

   There are two causes for that.
   One is because of the difference in luminosity, outside being brighter than inside.
   
   The second cause is the keyhole effect. When you look from inside to outside, you are closer to the curtain and you can see more. When you look from outside the distance from you to the curtain is greater and you cannot see very clear.
   The two effects combined give you more privacy.

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3. 58

   carol2050posted 12 years ago

   The whiteness of the lace reflects the sunlight and causes pupils to contract to keep too much glare out of your eyes and this makes it difficult to see through the tiny dark openings in the lace. The reverse is true at night. It is easy to see inside while it is nearly impossible to see the anything in the dark outside.

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4. 0

   Mr Knowitallposted 12 years ago

   The curtain does not reflect enough light from its inner side to interfere with the much stronger light reflected from objects out of doors. On the other hand, its outer surface is much more strongly lit than things inside the room, and the light reflected from it overcomes the light reflected from them.

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