Both are correct.. here's a good illustration...
http://www.astromart.com/articles/article.asp?article_id=30 (good article
too!)
However, for a quick measurement, the card works fine... just aim the scope
at the moon and compare the resulting circle to the one on the card.
RO
----- Original Message -----
From: "Richard Crisp" <rdcrisp@earthlink.net>
To: "The Astronomy Connection" <sf-bay-tac@seds.org>
Sent: Tuesday, July 27, 2004 1:49 PM
Subject: Re: [TAC] Exit Pupil size?
> i agree with Joe
>
> another way to get the same thing is to take Scope focal length *
> 1/Magnification
>
> Magnification = fl of scope/fl of eyepiece
>
> Focal ratio = focal length of scope / aperture diameter
>
> simple algebraic manipulation will give the result Joe cited
> rdc
>
>
>
> ----- Original Message -----
> From: "Joe Huber" <joe@huberfamily.org>
> To: "'The Astronomy Connection'" <sf-bay-tac@seds.org>
> Sent: Tuesday, July 27, 2004 1:43 PM
> Subject: RE: [TAC] Exit Pupil size?
>
>
> > I believe the calculation is the eyepieces focal length / F ratio of the
> > scope.
> >
> > -----Original Message-----
> > From: sf-bay-tac-bounces@seds.org [mailto:sf-bay-tac-bounces@seds.org]
On
> > Behalf Of LeFevre, Paul
> > Sent: Tuesday, July 27, 2004 1:36 PM
> > To: The Astronomy Connection
> > Subject: RE: [TAC] Exit Pupil size?
> >
> >
> > Mark,
> > I got one with my TeleVue Radian eyepiece...don't know if Al still puts
> 'em
> > in there, but if you've got a Radian box around, open it up and see :)
> >
> > Paul
> >
> >
> > -----Original Message-----
> > From: sf-bay-tac-bounces@seds.org [mailto:sf-bay-tac-bounces@seds.org]On
> > Behalf Of Mark Wagner
> > Sent: Tuesday, July 27, 2004 1:32 PM
> > To: tac
> > Subject: [TAC] Exit Pupil size?
> >
> >
> >
> > Is there such thing as a pupilometer, so I can measure the size of my
exit
> > pupil?
> >
> > Thanks....
> >
> > Mark
> >
> >
> >
> >
> >
> >
Received on Tue Jul 27 14:11:49 2004