artificial star test

Hi,
Ok here goes. I hope I did it right. I took an L.E.D. flashlight and covered it with an ep cover. I took a thumb tack and made the hole. I moved my scope about 150ft away.
At 225x it was very hard to make out the diffraction ring but it was there. It did seem to go all around, but as it was so faint my eyes were playing tricks and I kept thinking that the diff ring did not go quite around. I bumped it to 450x (2x barlow Knight owl) and boy was it evident that the diffraction ring DID go around the "Airy"
disc (although at that power there was some tubulance evident).
Anyway, does it sound like I did anything wrong in the artificial star set up? I only tested at focus (although the few seconds that I did an out of focus test the in and out images looked good but I didn't concentrate on them)

Take a picture with your digital camera held up to the eyepiece, inside, outside and at focus. Like they did here in these tests (from 3rd one down): http://homepage3.nifty.com/cz_telesco/syoutenzoutest.htm

Rolando

The pinhole should be smaller than the Airy disk to
get a good test. Can't quite tell how large your
pinhole is from the description. For a 4" refractor
(1 arcsecond resolution) and 150 feet you'd want the
pinhole smaller than about 0.005". It seems likely
the thumbtack would make a hole much larger than this.

Another approach is to use an "optical" pinhole where
a light of finite size is strongly de-magnified using
stacked Barlows or a short focal length eyepiece.
A 0.5" light source using a 6mm eyepiece as a de-magnifier
three feet away will give you an effective diameter
of about 0.5"/(36/.25)=0.0035"