At 01:59 PM 8/14/2008, chris1011@... wrote:

In a message dated 8/14/2008 12:09:24 PM Central Daylight Time,
astrovale@... writes:

Sorry Rolando, but I do not use Maxim but CCDSoft.

Then you're going to have loads of fun trying to get it to guide. Maxim has
so many tools to make it an easy enjoyable task. Good graphs to help you
determine where problems are.

Roland: many users have said that (for reasons unknown to me) CCDSoft actually seems to guide a bit better than Maxim. I cannot imagine why as the algorithms are likely similar. I would think the problems at low dec are likely due to what Joe Mize suggested - extinction and scintillation.

The only suggestion I'd have is to calibrate at around the celestial equator, and then when you go lower just increase exposure time on the guider to brighten the guide-star. One could play with the aggressiveness so as to not chase scintillation. And I guide binned 2x2 as I imagine most do.

I use your 7" f/7 and can guide 20 degrees or less of the southern horizon without problems, although I rarely shoot there ....


Dave