"Judah" wrote in message
. ..
No, I mean in MegaPixels.

That depends on both your estimate of angular resolution as well as your
estimate of the high-resolution field of view. Both vary considerably.

As an example, let's say that for the purpose of your question, we consider
only the field of view attributable to the fovea (the part of the eye that
has only cones, and no rods...this is considered the limit of
"high-resolution" vision...you can see a much wider field of view than this,
but without nearly the same detail as in the center of your vision). A
quick Google search turns up estimates of foveal field of view between 4
degrees and 15 degrees. So already we have quite a discrepancy of
estimates.

If we accept the 1 minute of angle estimate for angular resolution, that
gives us between 240 and 900 units of vision across the field of view. Call
those the equivalent of pixels, and assume a perfectly circular visual
reception, and you get between 45K and 636K "pixels". So in megapixels,
that's between 0.045 and 0.636.

That said, this is a pretty simplistic analysis of the equivalent in
megapixels of human vision. Human vision is different than digital vision
in a variety of ways, and a direct mapping such as shown above is leaving
out a lot of other factors that may affect total effective resolution. But
at the very least, this gives you a ballpark minimum starting point.

Also keep in mind that a digital camera may or may not have a lens capable
of resolving in perfect detail the total resolution available on the image
detector (usually a CCD). So you may have an 8MP camera, but when you look
at an image zoomed on a computer screen at a
one-display-pixel-per-image-pixel ratio, you may find a variety of artifacts
in the digital image.

So basically, human vision may be better than the theoretically calculated
resolution, while a digital camera may have less than the theoretically
calculated resolution. It's really hard to compare in a true
apples-to-apples way.

Pete