6 Sep
2011
6 Sep
'11
8:54 a.m.
On 9/6/11, Chuck Hards <chuck.hards@gmail.com> wrote:
On 9/6/11, Chuck Hards <chuck.hards@gmail.com> wrote:
If you want to make a small, dedicated white-light solar scope, you can install the filter material JUST behind the objective.
OK, before someone else posts it, it works for Gregorians too.