A method for producing a welded joint in a joint gap and process observation apparatus

In the production of a welded joint between the material flanks (9) in a joint gap (2) of a metallic workpiece (1) using a welding beam generator, with a welding beam (4) from a first side of the metallic workpiece (1) on the joining gap (2) is directed to achieve a complete weld of the material flanks (9) over the entire depth of the joint gap (2), and an optical detection means (5), with a surface facing away from the welding beam generator surface of the workpiece (1) from a second side of the the workpiece (1) is mapped to optically detect a resulting during the welding process molten bath (10) and evaluated with an evaluation stage, a process of observing the welding process for quality assurance is carried out in a simple manner, at the same time that the optical detection means (5) and the evaluation stage the location of the molten bath (10) and the position of the Fug espalts (2) is determined and the relative position to one another as a parameter for the adjustment of the positioning of the welding beam (4) relative to the joint gap (2) is provided.