Search found 5 matches

by cbbella
Fri Jul 30, 2021 1:17 pm
Forum: General Discussions
Topic: Sky brightness measurement
Replies: 6
Views: 1832

Re: Sky brightness measurement

Okay I'll give that a try Robin

Thanks
by cbbella
Fri Jul 30, 2021 12:13 am
Forum: General Discussions
Topic: Sky brightness measurement
Replies: 6
Views: 1832

Re: Sky brightness measurement

Hi Robin, when doing the sky brightness measurement should I do the measurement for each filter I use like h-alpha, Oxygen and sulphur. I ran the background test with my OIII filter in place and it started doing various exposures of 40sec, 2mins, 8mins and then 17mins at which point i cancelled the ...
by cbbella
Thu Jul 01, 2021 10:13 pm
Forum: Non-Astro Imaging
Topic: reticule/image not centering
Replies: 4
Views: 30067

Re: reticule/image not centering

ok i'll give that a try Robin

thanks
by cbbella
Wed Jun 30, 2021 3:04 pm
Forum: Non-Astro Imaging
Topic: reticule/image not centering
Replies: 4
Views: 30067

Re: reticule/image not centering

hi Robin, the primary mirror is blocked off by a white sheet of paper down the tube and a brown piece of paper is opposite the focus tube for contrast so what the camera is seeing is the white sheet of paper in the secondary mirror and the outer ring is the focus tube. everything seems to be sitting...
by cbbella
Wed Jun 30, 2021 11:28 am
Forum: Non-Astro Imaging
Topic: reticule/image not centering
Replies: 4
Views: 30067

reticule/image not centering

hi, i'm trying to collimate my skywatcher 200p newtonian and i'm following Astronomy Shed's video on "Advanced Newtonian Collimation" https://www.youtube.com/watch?v=8ROvNH5uwDo&t=922s when i turn on the crosshairs or circle reticule, the image of my focus tube doesn't seem to be centr...