Universal viewing camera for SAO RAS BTA

The development, creation, and implementation of highly sensitive observing systems both for the observing complexes and round-the-clock monitoring of sky transparency and cloudiness, are carried out at the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS). The latest development is the universal viewing camera presented in this work, mounted on the outside of the 6-meter telescope (BTA) prime focus cage (CPF) and monitoring a $4^\circ$ field. This system looks at the sky area where an object under study in BTA observations is located, i.e., the CPF viewing camera is always directed to the same sky field at which the BTA is pointed. And the images are obtained in real time, regardless of the BTA observing program and the complexes in one of the three foci involved.