İnsan gözü kaç megapiksel? -How many megapixels equivalent does the eye have?

İnsan gözü kaç megapiksel?-How many megapixels equivalent does the eye have?

The eye is not a single frame snapshot camera. It is more like a video stream. The eye moves rapidly in small angular amounts and continually updates the image in one's brain to "paint" the detail. We also have two eyes, and our brains combine the signals to increase the resolution further. We also typically move our eyes around the scene to gather more information. Because of these factors, the eye plus brain assembles a higher resolution image than possible with the number of photoreceptors in the retina. So the megapixel equivalent numbers below refer to the spatial detail in an image that would be required to show what the human eye could see when you view a scene.

Based on the above data for the resolution of the human eye, let's try a "small" example first. Consider a view in front of you that is 90 degrees by 90 degrees, like looking through an open window at a scene. The number of pixels would be
90 degrees * 60 arc-minutes/degree * 1/0.3 * 90 * 60 * 1/0.3 = 324,000,000 pixels (324 megapixels).
At any one moment, you actually do not perceive that many pixels, but your eye moves around the scene to see all the detail you want. But the human eye really sees a larger field of view, close to 180 degrees. Let's be conservative and use 120 degrees for the field of view. Then we would see
120 * 120 * 60 * 60 / (0.3 * 0.3) = 576 megapixels.
The full angle of human vision would require even more megapixels. This kind of image detail requires A large format camera to record.

burası da devian art'tan alıntı:
Your Eye's "megapixel" Resolution
The average human retina has five million cone receptors on it. Since the cones
are responsible for colour vision, you might suppose that this equates to a five megapixel equivilant for the human eye.

But there are also a hundred million rods that detect monochrome contrast, which plays an important role in the sharpness of the image you see. And even this 105MP is an underestimate because the eye is not a still camera.

You have two eyes (no kidding!) and they continually flick around to cover a much larger area than your field of view and the composite image is assembled in the brain - not unlike stitching together a panoramic photo. In good light, you can distinguish two fine lines if they are seperate by at least 0.6 arc-minutes (0.01.Degrees).

This gives an equivilant pixel size of 0.3 arc-minutes. If you take a conservative 120 degrees as your horizontal field of view and 60 degrees in the vertical plane, this translates to ...

576 megapixels of available image data.

Curiously - as a counterpoint to this - most people cannot distinguish the difference in quality between a 300dpi and a 150dpi photo when printed at 6x4", when viewed at normal viewing distances.

So: although the human eye and brain when combined can resolve massive amounts of data, for imaging purposes, 150dpi output is more than enough to provide adequate data for us to accept the result as photographic quality.

But don't forget that women have more cones and men have more rods - I kid you not.Therefore the ladies see colours brighter than gents but can't see as well when it gets dark.

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