For astrometric purposes, dark frame and flat field calibration is recommended.
For astrometric purposes, dark frame and flat field calibration is recommended.
出于天文测量要求，暗场图和平场图校准是被推荐的。
For astrometric purposes, dark frame and flat field calibration is recommended.
出于天文测量要求，暗场图和平场图校准是被推荐的。