Hi Lester
With The Sky 6 Pro I used to have the USNO-A2.0 database, a catalogue of 526,280,881 stars that went down to around mag 19. It was a 6 GB free download from
http://tdc-www.harvard.edu/catalogs/ua2.html although I don’t know if it is still available.
TheSkyX Pro now has an Add On product distributed on a USB hard drive that can be purchased from the Software Bisque Store, which again goes down to around mag 19 although it only works with The Sky X and not The Sky 6 and it costs around US $220.
Cheers
Dennis