I would be a bit wary of "slowly screw eyepiece out from barrel" sounds like you are unscrewing the eyepiece optics from the nose-cone and risking having the eyepiece optics fall off. High power eyepieces like 9 and 6 are very difficult to use as the "seeing" that is how stable the atmosphere is rarely is good enough. You may find using a 12mm or bigger with 2.5x Barlow easier to use.
Give some consideration to Televue Plossl eye pieces, they are moderately priced and heaps better than what came with my dob.
All the above with a grain of salt as I am mainly interested in photography.
