----- Original Message -----
From: "Patrick J. Madden" <RevPJMadden@...>
To: <guide-user@yahoogroups.com>
Sent: Friday, January 25, 2002 7:25 PM
Subject: Re: [guide-user] Fw: 7observing


> Georgiana,
> What is the advantage of stacking 10 3-second images over 1 30-second
> image?

"Guiding" is the simple answer. Even the poorest of drive motors will
generally produce a satisfactory 3 second exposure, but you need a good
sturdy mount and a decent drive system to get a good 30 second image.

Regards,

Chris
---------------------------------------------------------------
Chris Marriott, SkyMap Software, UK
e-mail: chris@... Web site: http://www.skymap.com
Astronomy software written by astronomers, for astronomers