Application Research for Astrometry.net and SCAMP in Astrometric Calibration

In order to explore the differences in the applications of Astrometry.net and SCAMP in astrometric calibration as well as the differences in the calibration results obtained by running them in different processes, we first introduce the working principles of the two suits of software, and then do astrometric calibration to 100 images from the ZTF survey in 4 difference processes, taking Gaia DR2 catalog as the reference catalog. The calibration results including those given by ZTF itself are compared in terms of total time consuming, catalog matching, and coordinate RMS deviation. The results show that Astrometry.net can quickly calculate rough linear calibration results, while SCAMP can quickly perform distortion correction based on the former. The combined calibration process averagely takes only 1 second, and the average right ascension and declination RMS deviations are less than 70 milliarcseconds, which is better than the calibration result only using Astrometry.net. Therefore, using Astrometry.net and SCAMP in combination can achieve faster and more accurate astrometric calibration, which may be applied to data reduction of time-domain projects nowadays.