The Human Eye and Mind

I was wondering; what is the average resolution of the visual field of a Human Being?

Is there a way to determine this?

Also, I was curious as to the 'frame rate' of the visual 'movie' we experience in our minds, not to be confused with the frame rate of the average film.

Thank you, and I really do look forward to your replies.

www.swift.ac.uk...
Check out page two of the pdf


www.clarkvision.com...

Visual Acuity and Resolving Detail on Prints

How many pixels are needed to match the resolution of the human eye? Each pixel must appear no larger than 0.3 arc-minute. Consider a 20 x 13.3-inch print viewed at 20 inches. The Print subtends an angle of 53 x 35.3 degrees, thus requiring 53*60/.3 = 10600 x 35*60/.3 = 7000 pixels, for a total of ~74 megapixels to show detail at the limits of human visual acuity.

The 10600 pixels over 20 inches corresponds to 530 pixels per inch, which would indeed appear very sharp. Note in a recent printer test I showed a 600 ppi print had more detail than a 300 ppi print on an HP1220C printer (1200x2400 print dots). I've conducted some blind tests where a viewer had to sort 4 photos (150, 300, 600 and 600 ppi prints). The two 600 ppi were printed at 1200x1200 and 1200x2400 dpi. So far all have gotten the correct order of highest to lowest ppi (includes people up to age 50). See: www.clarkvision.com...

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.

[edit on 14-2-2010 by DaRAGE]

[edit on 14-2-2010 by DaRAGE]

[edit on 14-2-2010 by DaRAGE]

That was very informative. Thank you so much.

It's an interest of mine, and any input is always appreciated.

reply to post by Unrealised


To answer your frame rate question here is some information from wiki.

en.wikipedia.org...

The human visual system does not see in terms of frames; it works with a continuous flow of light/information.[citation needed] A related question is, “how many frames per second are needed for an observer to not see artifacts?” However, this question too does not have a single straightforward answer. If the image is switching between black and white each frame, then this image will appear to flicker when the pattern is shown at rates slower than 100 frames per second. In other words, the flicker-fusion point, where the eyes see gray instead of flickering tends to be around 60 Hz. However, for fast moving objects, frame rates may need to be even higher to avoid judder (non-smooth motion) artifacts. And the retinal fusion point can vary in different people, as well as depending on lighting conditions.

Although human vision has no "frame rate", it may be possible to investigate the consequences of changes in frame rate for human observers. The most famous example may be the wagon-wheel effect, a form of aliasing in time, where a spinning wheel suddenly appears to change direction when its speed approaches the frame rate of the image capture/reproduction system.

Different capture/playback systems may operate at the same frame rate, and still give a different level of "realism" or artifacts attributed to frame rate. One reason for this may be the temporal characteristics of the camera and display device.