The average human retina has five million cone receptors on it and 100 million rods that detect monochrome contrast. The cone receptors are responsible for color vision and the rods are play an important role in the sharpness of the image you see.

Both your eyes are continually flicking around to cover a much larger area than your field of vision and the composite image is translated in your brain. It’s similar to stitching together a panoramic photo. In good lighting you can distinguish two fine lines if they’re separated by at least 0.6 arc-minutes.

That would give you an equivalent pixel-size of 0.3 arc-minutes. All in all, the human eye has about 576 megapixels. Women have more cones than men do, and therefore see colors brighter than their male counterparts. However, due to this, men can see better at night.

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