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Fred,
Maybe you can give a reference for this other web list?
The explanation you suggest coinside with my own conclusions
when I was trying to think about this incredible case 30 years ago.
Alex.

On Wed, 16 Feb 2005, Fred Hebard wrote:

> Frank,
>
> I read recently on another list that the density of photoreceptors in
> the eye is not a limiting factor in its resolution, apparently because
> the eye can move.  Unfortunately, I don't have time right not to dig
> this out and put it up for review.
>
> Fred
>
> On Feb 16, 2005, at 2:05 PM, Frank Reed wrote:
>
> >
> >
> >  Alex, you wrote earlier:
> > "However there are well documented cases of much higher resolution.
> > (One person tested in XIX century had resolution of 1",
> > but this seems to be the world record. Several people were described
> > who could see the phases of Venus with naked eye)."
> >
> > I mentioned before that I was skeptical, and it only dawned on me
> > while I was throwing out last week's back-of-the-envelope calculations
> > that one arc-second resolution is literally impossible. The
> > diffraction limit is imposed by the laws of physics and gives a lower
> > limit of 15 arcseconds under the very best of circumstances (under
> > typical circumstances, this optical limit is about 30"). If Nature
> > chose to pack more cone cells into our foveas than one for every 15"
> > of angle across the retina, they would not yield higher resolution.
> >
> > Can anyone think of a loophole I've missed here? The diffraction limit
> > has some fuzziness of definition (there's a pun in there somewhere),
> > but I don't think it's enough to help.
> >
> > -FER
> > 42.0N 87.7W, or 41.4N 72.1W.
> > www.HistoricalAtlas.com/lunars
> >
>

   

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