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Cherokee wrote:
24 mm Konig and 24mm Konig + Ultima barlow. Do I have the wrong eyepieces for the "double-double"? Probably, unless you have exceptionally acute eyes. With the Barlow, you're looking at about 40x. For most people, that's a fraction of the magnification you need to split the Double Double. You're better off at around 80x or so. The stars are arranged something like this: .. . .. * .. .. .. .. .. .. .. .. .. .. .. .. .. ** (Use a fixed-width font. The periods at the left there are only to keep Google from collapsing the lines. I hope it works.) The northern pair of stars is a fifth-magnitude primary topped by a sixth-magnitude secondary. Both of the southern pair are of the fifth magnitude. Both pairs are separated by about two-and-a-half arcseconds (that's about 1/1,500 of a degree--that's why you need higher power!). The southern pair is actually a little tighter than the northern pair, but because the stars are of roughly equal brightness, they are a bit easier to split than the northern pair, where the dimmer star has a tendency to get lost in the glare of the brighter one. -- Brian Tung The Astronomy Corner at http://astro.isi.edu/ Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/ The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/ My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt |
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