Sorry to be starting a new topic yet again, hope I don't look like a post whore: I'm thinking about buying this barlow but first I have some questions. 1) Will I be sacrificing a lot of image quality (if any) in using a 3x barlow? My scope is a 12" Dob. 2) Will the barlow simply triple the size of the image I see without it, or will it make other things visible that weren't before? 3) Is it really worth it to buy a 3x barlow rather than a 2x? Thanks.