Re: Dark adaption and pupil size - an experiment (longish)

From: Chris.B (chris.b_at_mail.dk)
Date: 08/27/04 

Date: 27 Aug 2004 00:04:00 -0700

boo@fractalfreak.com (eric bazan) wrote in message news:<ca17eb03.0408231339.689f4579@posting.google.com>...
 
> My goal was to drink enough of the tea to get my pupils dilated,
> but not enough to incapacitate myself.
>
> I chose a very clear moonless night for my experiemnt. I went
> for a walk at a nature preserve I'm familiar with

Now there's a sensible move. Take a dangerous substance and then seek
out somewhere isolated to become ill and die unnoticed. :-)

Dark sky adaptation seems (in my own experience) to continue for some
hours after the initial change.

A dark sky helps. I can go out from the lit interior of the house and
still see the Milky Way's clouds and channels immediately without dark
adaptation. But the sky goes on getting brighter (grey) for at least a
couple of hours. Despite the fact that it is really getting darker
during my observing times. Yet contrast increases all the time.
Despite the apparent increase in sky brightness. So more and fainter
objects can be seen more readily. Either naked-eye or through the
telescope. This assumes no Moon, no lying snow and no extraneous
lights from the house. High, dense hedges now shield the telescope
(and most of the garden) from the occasional car headlights on the
quiet road 200 metres away. An enclosing observatory would no doubt
offer further (and quicker) dark adaptation. Since all the kit would
be to hand. Instead of having to collect it all together from various
(artificially lit) places beforehand.

Chris.B

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