In this document, we demonstrate how the CX-A can be used in drug screening. We go through the whole process from image acquisition to data analysis and interpretation. As a case study, we chose to test what extent the art of observing influences the outcome of our experiments; something too often ignored when running live cell experiments. We measured the effects on cell health of four different cell treatments (1) label-free imaging and vehicle; (2) label-free imaging and addition of Mitotracker; (3) fluorescence imaging at low intensity regime and addition of Mitotracker; (4) fluorescence imaging at high intensity regime and addition of Mitotracker, using EA.