Help needed.

Hi all,
I'm confused, either my astrostar software has some serious mistakes or I'm complettely mis-understanding the astronomical meanings. For example; M57 is listed as being 1.3 arc minutes in size, while C6 is listed as 22.0 arc minutes. I need a 3X Barlow to get C6 (Cats Eye) to look a reasonable size in my scope or on the CD chip, but with M57 (Ring Nebula) I manage a pretty good sized image, both visually, and on the CD chip without a Barlow. Am I understanding these sizes properly. My understanding is that C6 should be much larger tha M57, as it is covering more arc-minutes of sky than M57.
Can someone explain if the software is wrong, or is my understanding wrong?
Bill H.

Hi all,
I'm confused, either my astrostar software has some serious mistakes or I'm complettely mis-understanding the astronomical meanings. For example; M57 is listed as being 1.3 arc minutes in size, while C6 is listed as 22.0 arc minutes.

I think C6 is something closer to 22 arc SECONDS (Magnitude 8,3 - Size 22" x 16")

Here's a site which has photos and sizes of M57 and C6 so you can compare side-by-side;

home.planet.nl/~onielsen/ccd/pn-summer.html

Hi jhonan, thanks for that, I thought I had my understanding wrong. Looks like Meade need to get their homework done and rewrite their software. Quite appalling really. I checked those figures again and it definately says 1.3 minutes for M57 and 22.0 minutes for C6, it also claims 27.0 minutes for C15, whereas your link says 27 seconds.
Meade, I've lost my faith in you, time to scrub it and pay more attention to starry night pro.
Bill.

Hi Bill - I don't bother with the Meade Autostar suite. I use SNpro but even that is awash with errors, though probably not as many as Meade's.

TheSky seems to be the best choice, or use Aladin (on line and you probably need broadband )

Cheers

Dave

hi Bill,

a comprehensive catalogue of deep sky objects (and double stars) is available from the Saguaro Astronomy Club. Their downloads are at . . .

www.saguaroastro.org/content/downloads.htm

each file can be imported into a spreadsheet type program just be delimiting column separators. The databases are the templates used by a number of astronomy software vendors and considered quite reliable.

John

TheSky seems to be the best choice, or use Aladin (on line and you probably need broadband )
Cheers
Dave

Thanks everyone.