He couldn't have: there wasn't time, and Gates's eyes could distinguish nothing.

Now, let's get into how the eye can perceive these colors and distinguish them from each other.

Only then imagination could paint what the eyes did not distinguish.

Nevertheless, his piercing eyes could distinguish a figure upon the floor.

The old servant's poor eyes could distinguish but the forms of two men.

So much their eyes, long accustomed to the darkness, could readily distinguish.

But all three are quite different; and an eye which has once known, can thenceforth easily distinguish them.

The human eye can distinguish about 3 objects or features per second.

My eyes, dazzled with the outer light, could distinguish nothing.

The average human eye can distinguish about 500 different shades of grey.