An angiography system for angiographic examination or treatment of an organ, vascular system or other regions of an object of a patient is proposed. The system has an x-ray source and an x-ray image detector disposed at ends of a C-arm, a patient support table, a system control unit, an image system, and a monitor. The object contains two details hiding each other in the x-ray images depending on angulation of the C-arm. The system control unit has a device that detects a 3D dataset of the object registered to the C-arm and detects the information about a course of the object. The device calculates a desired and/or optimum angulation of the C-arm from the detected information and transfers the calculated angulation to the system control unit for adjusting the C-arm to the angulation.