I plan on heading up to north central Oregon next month to take in the total solar eclipse, and am considering buying a new lens to photograph it. Specifically, one of the Samyang or Bower 800mm f/8 mirror lenses that I see offered on eBay for ~US$250. I know some of you have experience with these lenses, and I'm hoping you might be able to give me some input, whether good or bad. I have no real use for a lens of that focal length other than for this one event. So I'll probably just turn around and sell it after the eclipse. But this is a fairly rare phenomenon (I've seen one other total eclipse down in Baja in 1991), and I don't want to find myself wishing I had better gear. So whadyathink?