NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: 2102-E Star Finder, Rev 9
From: Brad Morris
Date: 2009 Mar 3, 13:02 -0800
From: Brad Morris
Date: 2009 Mar 3, 13:02 -0800
Hi John I think I found the off by one problem. Along the way, I realized that I had originally made a horrific shortcut. The 57 navigational stars were only resolved to 1 degree in SHA and delination. I used my Nautical Almanac to enter these numbers to nearest 1/10th of a minute. I don't think this would make a terrific difference to the display, but it bothered me. So I fixed it. The extension line was easy, as is the arrowhead, I just haven't gotten around to it. Making a slider bar work backwards (enter the number and watch the slider bar move to the new location) is well beyond Excel, at least to my understanding. I could port this to almost any language under the sun, but keeping it in Excel leaves it accessible to most, and keeps it open source. I wanted folks to see HOW it worked, not just see it work! I flipped the controls around, and added some simplistic instructions. I really like being able to move the blue templates from +90 to -90. This is the non-intuitive, completely surprising fun part of the 2102E. My only disappointment is in the shape of the longitude lines. Excel runs out of gas when you have too many points to be manipulated, so I traded speed for beauty. I realized that nobody would use it if it was too pokey slow. I added Polaris and the "outer limits". When in the Southern Hemisphere, of course Polaris rotates, just as it does in the Northern Hemisphere, its just hard to see there. It's just a demonstration that the N Pole in the Southern Hemisphere is a circle, not a dot! Best Regards Brad Brad --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---