- Dec 17, 2012
Because in nighttime conditions your eyes see more into the blue spectrum (scotopic vision). For example, if you look at the ground at night, after your eyes have adjusted, it'll look more blue to them. There isn't actually more blue light, but your eyes are most sensitive to that wavelength under such conditions.On a side note, I never understood why blue LEDs are used to simulate moonlight. Even aquarists often use blue LEDs on their tank for the moonlight effect. I only used white LEDs for the moonlight on my tank. Since when did we have a blue moon?