Eyesight resolution

The reason our vision never pixelates is that we compensate by moving our eyes. In other words, we scan and rescan the image as many times as necessary.

The electric signals produced in the eyes are sent to the brain where they are processed. The various scans are combined into the final image.

Whatever pixelation may still remain is then "discarded" by the mind by combining the "bitmap" into the illusion of a continuous tone image.

Human mind is very good at picking up essential information and discarding any redundancy.

Well the brain can theoretically perceive near infinite resolution so it's just a matter of your eyes ability to register and send detail.

Your eye initially sees low-res blobs of colour. It sees more detail the longer it concentrates on an area. However detail is seen quicker in the frontal region of your field of vision, which is generally regarded to be about 30^o on most people.

Spinning round in a circle and you'll just see blurs. Stop and stare and you'll gradually gain a more detailed view. Most people reach their 80% of their maximum resolution after about 1 second and reach their best after two or three.

The instant resolution of the eye is only about 100²<->200². Most people can see a maximum of 5000². There have been freaks who can see an estimated 50,000².

I remember a story about a hustler who tricked people to hold cards behind his head. He would be able to tell the number and suit from the reflection in the crowds eyes.

disclaimer: this is all from fuzzy memory, apologies

Human vision is processed on the retina of the eyeball using two different types of receptors, the rods and cones. Rods measure the brightness of the light hitting them (black-and-white vision), and cones measure the amount of either red, green, or blue light (color vision).

Resolution of human vision is difficult to quantify because the density of rods and cones changes, independently, across the entire retina. You have a higher density of cones near the fovea of your retina than around it, but rods are nearly equally distributed throughout the entire retina outside the fovea. The fovea is where vision is sharpest, the center of what you're looking at.

The area considered the "central retina" is a circle 6mm in radius around the fovea, an area of about 113 mm², and your entire vision is a circle about 21mm in radius, or 1385 mm². The average human has about 75,000 cones in the fovea of each eye, and comparatively few outside. Rods, however, average about 100,000 per mm² (400,000 per mm² at maximum density), which would mean you have about 140 million across your entire retina. Pretty hi-res, that.

Actually, there is no "resolution" per se with regard to human eyesight, as the world is not generated (or viewed) as a raster.

The universe is built using vectors. The best analogy to use would be "real-time vectoring" as you can move anywhere, and your brain is constantly recalculating your position so:

1. You don't fall over (lose orientation) when you move
2. You don't bump into anything

The laws of physics determine how things work, how they're constructed, and how they behave in the world. This includes movement, stability, cohesion, and all that jazz. A can of Lysol consists of the same angles and dimensions no matter where it is or from what angle it is being viewed. That's why you are able to pick up that can and read the small print on the back by bringing it closer to your eyes. The vectors aren't changing; our eyes are just adjusting to the new orientation.

Now if you were to take that can of Lysol and throw it across the room, it's up to the laws of physics to calculate the changes in its movement. And physics, of course, is vector-based. When the can lands, you won't be able to read the text anymore, as the vectors have seemingly muddled together due to them being too far away on which to focus. The can is visually smaller, too. Conversely, when the can is too close, our eye muscles cannot exceed their limit on focusing. Thus, it becomes blurry.

The information hitting our eyes is limited only by c, then slows even further while our brains recalculate the new information. Therefore, I'd be more interested in the refresh rate of our eyesight. That is, how many times per second the brain can possibly resample our field of vision to pick up, and comprehend movement.

The diffracation limit of a telescope is a function of the wavelength of the light and the diameter of the telescope. This tells us the angular seperation below which two objects cannot be distinguished because the diffraction pattern caused by the circular aperture obscures the objects. The human eye can be considered as a primative telescope. The formula is approximatly.

D = (1.22 x wavelength)/aperture

Taking the aperture to be 2mm and the wavelength to be 555 nanometers the calculation yields an angle of about 1.7 arcmin, the best telescopes in the world aim for sub arcsecond resolution.