Re: Need help -- Wheelchair bound friend interested in astronomy

ezarenski_at_gilbaneco.com
Date: 02/06/05 

Date: 6 Feb 2005 11:41:09 -0800

msimmonsmcse@yahoo.com wrote:
> Thanks. I suggested a 7x50 cause its easy to hold in your hands as
> opposed to the giant astro binos.
>
>
> ezarenski@gilbaneco.com wrote:
> > I would not recommend a 7x50 binocular as a first binocular. This
is
> a
> > specialized binocular and it's performance will likely be
compromised
> > unless all these necessary conditions are met.

If hand holding is expected, you might want to consider 8x40, 8x42,
10x42 up to 10x50. But a binocular with a 7mm exit pupil (7x50, 9x63,
10x70) has special considerations and should probably not be considered
as a first choice, unless of course you can satisfy all the
requirements. Few people can.

Magnification makes it harder to hold the image still, but keep in mind
you see a lot more (with few exceptions) with higher magnification. A
12x50 will see 0.75 magnitude deeper than a 7x50. That's an awful lot,
considering 1.0 magnitude is 2.5x the light. If you're going to
consider mounting these binocs, don't go small on the magnification.

edz