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<p>[QUOTE=&quot;-jeffB, post: 2683609, member: 27832&quot;]The analogy is more apt than you think. Under <i>completely</i> dark skies, with completely dark-adapted <i>normal</i> vision, you can see <i>at least</i> 12, and possibly more. (Limiting magnitude for the unaided human eye under ideal skies was typically taken as 6; there are 12 Pleiades brighter than that. Many people can see down to 6.5 if conditions are good enough.)</p><p><br /></p><p>But people today are more interested in 24-hour &quot;security&quot; lighting, and loath to drag their eyes away from their screens for half an hour or more to get fully dark-adapted anyhow. So, when I look up at night from my house, I&#039;m lucky to make out more than 4. But my corrected vision still gets graded as &quot;uncirculated&quot;, er, &quot;20/20&quot;.</p><p><br /></p><p>Edit: No, Kurt, I <i>don&#039;t</i> want to hear about the night skies where you are. It&#039;s quite enough of a sore subject with me as it is. (Actually, while you&#039;re bound to have better skies than me, you&#039;re still well within the light dome for Philly. New York and Baltimore, too, for that matter.)[/QUOTE]</p><p><br /></p>

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