Re: distant wires

[T3D John Ohrt <johrt@xxxxxxx>]

T3D john bercovitz wrote:

> Consider that the receptors in the eyes are a couple of microns on
> center at closest.  That comes out to about half a minute of arc
> of  resolution.  Also consider that the resolution of the eye
> peaks (because of a balance of aberrations and diffraction and
> other factors) at a pupil diameter of 3 mm.  Remembering the
> Rayleigh criterion and the simple rule which ensues that the
> angular resolution of an optical system such as this is
>
> (115 second of arc - mm)/(diameter of the entrance pupil in mm)
>
> you find that the resolution of the eyes is 115/3 which is again
> about half a minute of arc.  This is in a perfect eye under the
> best of conditions (high contrast object).  If the eye has any
> problems at all, there is a reduction in its resolution which
> leads us to the ordinary eye's resolution of 1 minute of arc.

While I can resolve just under 1 minute of arc under moderate
contrast conditions, I cannot resolve much more a high contrast
conditions, like Venus or Jupiter on a dark night.  If I could, I
would notice that they are spatially distributed and not a point
source.  In fact, scientists are very skeptical of anyone who says
they can, and there are people with much better eyesight than mine.
OTH, an object 2 moa at moderate contrast is easily discerned as
spatially distributed.

I suspect that there are other effects in that eye that degrade
resolution above 0.5 moa than just the ones examined so far.

Regards,

--

John Ohrt * Toronto * ON * Canada






------------------------------