  The 80-cm azimuthal telescope is newly mounted at Yaoan Station, Purple
Mountain Observatory in 2018. The astrometric performance of the telescope is
tested in the following three aspects. (a) The geometric distortion of its CCD
attached. It is stable in both a single epoch and multi epochs. Eight
distortion solutions are derived over about one year. The maximum values range
from 0.75 to 0.79 pixel and the median values range from 0.14 to 0.16 pixel.
(b) The limit magnitude of stars. About 20.5 magnitude (Gaia-G) stars can be
detected with Johnson-V filter exposured in 300 seconds. The astrometric error
of about 20.5 magnitude stars is estimated at 0.14 arcsec using the fitted
sigmoidal function. (c) The astrometric accuracy and the precision of stacked
fast-moving faint object. 24 stacked frames of the potentially hazardous
asteroid (PHA) (99942) Apophis are derived on April 14 and 15, 2021 (fainter
than 18 mag) based on the ephemeris shifts. During data reduction, the newest
Gaia EDR3 Catalog and Jet Propulsion Laboratory Horizons ephemeris are
referenced as theoretical positions of stars and Apophis, respectively. Our
results show that the mean (O-C)s (observed minus computed) of Apophis are
-0.018 and 0.020 arcsec in right ascention and declination, and the dispersions
are estimated at 0.094 and 0.085 arcsec, respectively, which show the
consistency of the stacked results by Astrometrica.
