Students' and pre-service teachers' conceptions of scientists have been assessed in a variety of studies. One of the most commonly used instruments is the Draw-A-Scientist Test (DAST) which offers the advantage that no verbal skills are needed by the participants. In some studies, methodical challenges related to the DAST have been discussed; for example, the lack of drawing abilities among the subjects or the impact of the prompt itself on the drawings which lead to invalid interpretations. This study aims to evaluate the eligibility of the DAST or similar instruments to validly assess conceptions of scientists and their work. Pre-service science teachers in two cohorts (N[subscript 1] = 79, N[subscript 2] = 101) were prompted to draw their conceptions of a scientist, the location at which the scientist is working, and his/her scientific activity. The participants of cohort 2 were also asked to give written descriptions of their drawings and information on the conditions while they were drawing. From the results, several points of methodical criticism can be made which question the valid interpretation of DAST-drawings. Instead of using the DAST, we suggest developing and evaluating other formats, such as open-ended or closed-ended instruments which could produce a more validly interpretable assessment of individuals' conceptions in this field.