Thanks everyone for your detailed replies.... Will give these options a try....
as a test last night I slewed to M83, and took a frame, uploaded to
http://nova.astrometry.net/ .... to my delight, it reported M83 was actually near frame centre.... the old Gemini is pointing better than I thought!
M83 -- RA 13h 37m 00.9s; DEC -29deg 51' 57"
centre of my frame reported as - 13h 48.711s; DEC -29deg 56' 23"
only missed by several minutes.....