15 Aug
2011
15 Aug
'11
10:16 p.m.
I was totally shocked, both by the original message, and Patrick's notes about cheap telescopes in the comments, that it is possible to have a primary filter at the eyepiece. It seems to me that anyone who ever used a magnifying lens to set a leaf on fire would know not to have a filter in place after the sunlight has been focused by lenses or mirrors. Live and learn, I guess.