18 Oct
2011
18 Oct
'11
9:57 a.m.
On 10/18/11, Hutchings, Mat (H USA) <mat.hutchings@siemens.com> wrote:
Aw, come on, you can brave the cold at night in the winter!
Yeah, to a point, but then again, I am designing a heated observatory, so that's gotta tell you something... ;) Re: Ronchi testing With much experience, you can tell a lot with the Ronchi test. I used to hang-out with a local optical manufacturer, and we'd look at mirrors through the Ronchi. I would point-out problems that he had to stare and stare at, and most of the time he'd say "yeah, maybe..." until we star-tested it. Then he'd admit that I detected it with the grid.