Re: ATM Exit Pupils & Big Scopes

["James W. Burrows" <burrjaw@halcyon.com>]

On Wed, 14 Aug 1996, M.E. Germann wrote:

> Exit Pupils & Big Scopes --
> For those embarking on big projects it might be useful to
> know your own personal entrance pupil. . .and what it is
> likely to do (change) over the next decade or so.

I've measured mine and strangely enough, the left pupil is slightly larger
then the right, 5.5 mm vs. 5.0 mm.  Unfortunately, my right eye is better
"trained", the habitual eye for peering through optical instruments for 50
years (is that why it's smaller?).

BTW, you don't have to buy a pupil-measurer from S&T, just prick pinholes
5, 5.5, 6, etc. mm apart in a piece of paper, go into a closet, almost
close the door so just a crack of light shows, hold the paper close to
(each) eye, and see which pair of fuzzy balls of light just touch (do a
ray-trace to check this statement).

BTW2, the pupil reaction time to changes in light level is less than a
second, compared to the retinal reaction time of half an hour - you don't
have to stay in the closet very long...

     Jim Burrows    206-244-2933
     E-mail:        burrjaw@halcyon.com
     Seattle:       WGS84 lat 0.828547, long -2.135692 (rad)