Today, the digital zenith cameras have the highest accuracy and efficiency in determining the components of the deflection of vertical. The error of modern zenith cameras is 0.1–0.3 arcsec, and the measurement time at a single point does not exceed 1 hour. Zenith cameras are fully automated and allow measurements with a discreteness of hundreds of meters—the first kilometers. The article presents the main features of the zenith camera of the FSUE ‘‘VNIIFTRI,’’ as well as current work on its modernization and testing.
Murzabekov et al. (Mon,) studied this question.