The human eye really sucks compared to modern camera lenses.

The human visual system, on the other hand, far surpasses any modern camera system (lens, sensor, firmware).

• The human eye is only sharp in the centre. In fact, it's only sharp in one very, very tiny spot known as the fovea, which is a spot whose diameter is less than one percent of our total angle of view. So we have some serious corner softness going on.

  The human brain is able to correct for this, however. It instructs the eye to make very rapid movements all around a scene so that the sharp part in the middle darts around. The brain then has a pretty awesome in-body image stabilisation, because it takes all these rapid movements and stitches them together to make one, sharp scene - well, at least all the bits the eye landed on while darting around will be sharp.

• The human eye is quite sensitive to light, but at low light levels no colour information is available. In addition to this, the sharp part in the centre (the fovea) is less sensitive to light.

  Technically it's because the eye has separate photosites called cones for the three colours (red, green, blue), and another different type of photosite called rods that only captures black and white, but is much more efficient.

  The brain stitches all these together to create an excellent full colour image during the day, but even when it's really, really dark it comes up with a soft, colourless image made by all the rods.

• The eye only has one lens element and it produces terrible chromatic aberration in the form of purple fringing.

  Actually, this fringe is all in the very short wavelengths of light. The human visual system is least sensitive to these blues and violets. In addition to this, it's able to correct for that fringing that does exist in a few ways. First, because the human vision system is only sharp in the middle, and that's where there is the least chromatic aberration. And secondly, because our colour resolution is (outside the fovea) much lower than our brightness resolution, and the brain doesn't tend to use blue when figuring out brightness.

• We can see in three dimensions. This is partly because we have two eyes, and the brain can do amazing calculations relating to convergence between them. But it's also more advanced than that; as well as the "3D effect" you get from stereo vision, the brain can also reconstruct scenes in three dimensions even when looking at a two-dimensional photo of the scene. It's because it understands cues such as occlusion, shadows, perspective and size clues and uses all these to put together the scene as a 3D space. When we look at a photo of a long hallway we can see that the hallway extends away from us even though we don't have stereo vision, because the brain understands perspective.