Both of my eyes suffer from myopia and astigmatism. I can focus out the former when using binoculars or a telescope but not the later. I've worn glasses part time since I was about twelve years old. The tip off was trouble reading the blackboard. For years I resisted using spectacles when observing and put up with the astigmatism but I almost always use my glasses now. These days the only thing my eyes have going for them is a decent amount of focus accommodation and at forty years of age that might not last for long.
For those who suffer from myopia and wear spectacles (or might soon), Sky & Telescope ran an interesting article about night myopia in their September 2005 magazine. You can download a PDF version of the article here <
http://www.skyandtelescope.com/howto.../64352322.html>. I asked my eye specialist about night myopia when I last had a check-up and explained that I spent quite a bit of time outside at night observing or driving. In addition to a prescription for a new pair of normal spectacles (call them `day time glasses') he gave me a second prescription with an extra half a diopter of correction for night time use (call these `night glasses'). For me the extra correction does help. The difference isn't `hit you over the head huge' but I can see more detail at night, e.g., naked eye I see the Pleiades as a hazy blur, with my day time glasses I can pick out maybe five members, with my night glasses I can pick out seven.
For those who might be joining us `four eyes' there was also a thread here on IceInSpace a couple of years ago with general advice for things to look for in spectacles used for astronomical observing <
http://www.iceinspace.com.au/forum/s...d.php?p=352838>.
