Eye Acuity

How good are human eyes? On a clear night you can see the flame of a match up to fifty miles (80 kilometers) away.

One extraordinary South American Native teenage girl said she could see four of Jupiter’s moons without a telescope. When scientists asked her to draw the moon’s positions, she was accurate.

Whereas the human eye has much greater acuity near the center of the field of vision, a digital camera has uniform acuity. However, the human eye has been compared to a 137-megapixel camera. At the current rate of technological growth, your phone will be able to see better than you within eight years.

Do you wish your phone already had that capability? In a way it does: On iPhones, and most Androids, tap the main button three times, and your camera becomes a very good magnifying glass, even in low light conditions.