We ’ve all see photographs where the hoi polloi in the painting have spooky violent centre . These are photos taken at night with aflash . Where do the cerise optic descend from ?
The red color number from light that reflects off of the retinas in our centre . In many animals , including click , khat and cervid , the retina has a special reflective bed address thetapetum lucidumthat acts almost like a mirror at the spine of their eyes . If you fall a flashlight or headlamp into their eye at night , their eyes shine back with bright , white igniter . Here is whatEncyclopedia Britannicahas to say about the tapetum lucidum :
Humans do n’t have this tapetum lucidum layer in their retina . If you shine a flashlight in a person ’s eyes at dark , you do n’t see any sort of reflection . The flash on acamerais bright enough , however , to cause areflection off of the retina– what you see is the red colouring material from the blood watercraft nourishing the eye .
Many cameras have a " cherry eye diminution " feature . In these tv camera , the heartbeat blend in off double – once in good order before the picture is taken , and then again to in reality take the pictorial matter . The first flare make people ’s pupils to contract , reducing " red center " significantly . Another trick is to twist on all the lights in the way , which also contracts the pupil .
Another way to slenderize or excrete " red eye " in pictures is to move the flash away from the lens . On most small-scale cameras , the flash is only an inch or two away from the lens , so the reflection come right back into the electron lens and shows up on thefilm . If you candetach the flashand withstand it several feet forth from the crystalline lens , that helps a lot . you may also try bouncing the New York minute off the cap if that is an option .
For more picture taking tips , see the links on the next Sir Frederick Handley Page .
