I know my camera resolution but What is my eye resolution [or rather the human eye resolution]?
My digital camera resolution is 6 megapixels. What that mean?
The size of the image that camera takes is created basically by the sensor inside the camera. A digital camera create a 2d image made of a certain number of lines and colons of pixels. The number of pixels gives the resolution of the camera. So 6 megapixels is 6 millions of pixels or 6.000.000.
If you put that in a 3 by 2 format a 6 megapixels camera can give you an 3.000x2.000 pixels photo. In terms of printing this (despite the fact that is a 5 years old camera) this is a very good resolution and if you print at a good quality magazine a such an image can be 10"x7" or 30cm x 20cm - most of the people print at 6"x4" .
The eye resolution, if you can call it this way, consist of photoreceptor cells found in the retina. This cells are actually a type of neuron capable to transform the photons that hit them into signals. The number of this photoreceptors gives the resolution of the eye.
The photoreceptors mainly are of two types - rod cells and cone cells. The rods are the cells that are the most in the human eyes about 120 million compare to about 6 million cone cells, and those rods cells require few photons to produce a signal helping you to see in low light. The cones cells require a much more number of photons to produce an signal and are of tree types - these cells are responsible of color- every type trigger signal of o certain wavelength range of light. That why the dimmer the light the less of the colors you see because less cones cells trigger what you actually see.
Now a days almost any camera comes with 12 megapixels which can create an image of about 4.000 x3.000 pixels.
So what is the size of an image that our eye can capture? In about 120 millions pixels(120 megapixels or 120.000.000) you can fit an image of 15.000 x 8.000 pixles. Every split of a second when you look at something your eye and your brain process an 120 megapixels image.