Equatorial coordinates of the main axis of a ballistic camera can be determined from the elements of camera exterior orientation. The parallactic angle too, in the principal point of the plate, can be derived if, e.g., a spirit level has been conveniently mounted on the camera and used during the astro-photogrammetric observations. From two or more plates and by means of the parallactic angle both the geographical coordinates of the camera station can be determined with an expected accuracy of about $\pm 0^{\prime\prime},4$. A graphical solution is also presented in the paper.