Re: Star Testing using large disc

On Nov 5, 6:28 pm, Tenifer <tensorsur...@xxxxxxxxx> wrote:
I wasn't able to test it at an airy disc
because the sky was not clear enough . . .

As noted in Suiter's book, a silver sphere Christmas ornament and a
small flashlight can be used to create a point source under cloudy
skies or at night. During normal daylight testing, the glint of the
Sun off the sphere or a ceramic telephone pole insulator is used to
create an artificial star. I use a ball bearings because they are
smaller and make smaller glints (either from a flashlight or the
Sun). Thus, they can be placed closer to the telescope than a larger
Christmas tree ornament and the glint still has the angular size of an
Airy disk. See Suiter's book for details. My artificial stars look
like this -

http://gallery.utahastronomy.com/v/kurt/atm/007.jpg.html

http://gallery.utahastronomy.com/v/kurt/atm/008.jpg.html

Cloudy skies, either at day or night, is not a constraint preventing
the creation of a point source artificial star.

- Canopus56

.