Jeffrey--
Critical focus is for the CAMERA. Once you have
established proper focus for the Camera, using any
of a variety of methods-- (Kwik-Focus, knife-edge,
Inten-screen, etc.) to assure proper camera focus
you must focus your' off-axis guider by either a
focusable guide eyepice, or manually moving the
guide e.p. in and out of the holder to achieve
accurate focus. If you can't achieve focus by
moving it to it's outermost travel it may be
necessary to add an extension tube. Leave your
focus knob where it is once you have the camera
as sharp as possible! It may be necessary to
use a bright star to focus it, then move to the
object of target interest and find a suitable
guided star. Good luck!