For the promotion of students' learning in science, teachers must attend to critical classroom situations in which students express their ideas about scientific concepts and methods. The notion of professional vision is used to describe the skill of noticing situations that are relevant for learning and understanding. The present study contributes to solving the problem of whether professional vision with a physics-specific focus can be validly measured through the application of an instrument based on scripted instructional videos and a partially closed questionnaire. In three sub-studies, video vignettes, and items were developed, resulting in an instrument consisting of 19 items (EAP reliability was 0.698) through which physics-specific professional vision could be measured. Further analysis supported the construct validity of the instrument. It has been shown that physics-specific professional vision differed significantly according to the subject studied by pre-service teachers (i.e. physics and geography), indicating a physics specificity of the construct.