Electron beam (EB) welding is a process where a focused beam of electrons is accelerated in vacuum and directed at the workpiece. When those high-energy particles hit the material, they convert their kinetic energy into heat, enabling metals to melt and be joined. The process is used in various industries such as the aerospace industry, automotive industry and in medical technology. These are often either high-precision applications or welding tasks that require complex processing. It is therefore essential for the quality and reproducibility of the weld to have systems available for characterizing the electron beam. This is particularly challenging at high beam powers. There are several measurement systems for beam measurement, such as the DiaBeam System from ISF, RWTH Aachen, the two slit probe from TWI, Cambridge, or the rotary wire probing system. These systems have in common that the beam is deflected on a receiver (wire or Faraday cage). The captured electrons are then diverted via a measuring electrode. However, the sensitive electronics and thin apertures of the measurement technology cannot be used for higher beam powers. When the electrons are decelerated in the welding zone, the heat for welding and X-ray radiation (bremsstrahlung and characteristic radiation) is generated, which is normally undesirable and must be prevented from escaping from the electron beam welding (EBW) machine. However, it is also possible to use the X-ray signal to characterize the EB. In this work, an X-ray camera was developed that images the X-rays on a scintillator using a pinhole aperture according to the principle of a camera obscura. Using this camera system, housed in a cylindrical atmosphere box, the EB could be characterized, even at high power levels. For this purpose, the EB was recorded and measured at different heights. In this way, the smallest diameter (focus point) and the roundness of the beam could be determined. For the first time, the EB beam can be reliably measured even at high beam powers. The robust design of the X-ray camera, which is also not exposed to the EB, provides a reliable and user-friendly measurement system for characterizing the EB.