The aim of this study is to point out the similarity and differences of data processing based on either FRAP (Fluorescence Recovery After Photobleaching) or FLIP (Fluorescence Loss In Photobleaching) experimental techniques. The core idea, closely related to the sensitivity analysis, is based on discerning between relevant and irrelevant data. Presented mathematical model allows to visualize the mutual relation between the FRAP and FLIP methods. The whole concept resides in the processing of full spatio-temporal data instead of the space averaged time series (FRAP recovery curves). The method theoretically confirms the empirical knowledge, that the mobility of fluorescent molecules can be determined with both FRAP and FLIP methods (using the full data approach). Our analysis, based on the idealized theoretical case study, supports the conclusions of our recent experiments and thus it validates the reliability of our new approach. The presented finding are expected to be reflected into experimental protocol setup as well as we will continue working on the further enhancing the method of parameter identification.