seeding the database

[<aah@nofs.navy.mil>]

I'm holding off suggesting any seeding method
until I see how well the Mark IV performs at
a dark site.  The FASTT 8" and a similar CCD
gets to R=18 in 3.5min exposures,
so my guess is that I will be able
to double-detect down to V=16, which would be
a good match to UCAC (if there were a northern
counterpart), but much fainter than GSC.  The
USNO-UJ survey would be just about perfect since
it goes to 17th mag and down to the equator, but
then there still is the missing pieces of UCAC
south of there.  If my limiting magnitude estimate
is correct, then the only current alternative
is a magnitude-limited version of USNO-A2.0.
I think the better alternative, if the astrometry
is reasonable, is to just build a unique catalog
without seeding.
  My plans are to use only deep exposures during
dark hours, and only short exposures during moonlit
hours.  The lengths of these exposures is TBD,
depending on the shutter accuracy and sky background.
Arne