I am relatively new to this forum (and new to astronomy) and have gleaned a lot of great advice and info. I have an 8" Apertura Dobsonian that came with the 9mm and 30mm eyepieces. I bought a highly recommended 2" GSO 2X Barlow that has an adapter to fit the 1.25" lens.
I've been able to view the moon up close with the 2x Barlow and the 9mm installed and they seemed pretty sharp. I am able to view Jupiter with the 2X barlow and the 30mm and everything appears to be sharp. Things don't look so great when I remove the 2" 30mm EP and and put the 1.25" 9mm into the barlow (with adapter). I can't get it to focus as sharp. I am pretty certain it's because I'm not doing something right. Maybe there's too much focal length in the barlow and EP for it to be able to achieve the focal sweet spot? Do I need to use the 35mm extender tube at some point to make it focus on further objects? I tried adjusting the lengths of the barlow tube and EP position.
I found M13 last night after sweeping the skies for a good 15-20 minutes. with the 2X barlow and 30mm lens it looked like a small grey cloud. I attempted to get closer by putting in the 9mm EP into the barlow but I could not get it to focus and see any small pin point stars. Just a bigger out of focus grey cloud...
Am I missing something with regards to the 9mm and 2x Barlow combination?
I was thinking of maybe getting a 6mm Goldline EP that everyone recommends - can someone give me a link to one of those? I've been searching but not sure if my results are the correct EP...
Thanks for any advice!