advanced vx alignment astronomy astrophography astrophotgraphy astrophotography astro photography astrophysics avx barlow beginner beginner astronomer binoculars camera canon ccd celestron collimation coma corrector d5300 diy dobsonian dslr dso eclipse eyepiece field of view focus fov galaxy goto gso 8" newtonian f4 imaging introduction jupiter lens light pollution m31 m42 mak mars meade messier 30 messier 30 certificate milky way moon mount nasa newbie newtonian nexstar nikon orion planets polar alignment question reflector refractor saturn skywatcher solar solar filter solar system starinastar stellarium sun telescope telescope advice tracking zoom