1. An observation method comprising: capturing a sample and acquiring a plurality of captured images; extracting one or more regions to be observed from among the plurality of captured images acquired in the acquiring a plurality of captured images; classifying the one or more regions to be observed extracted in the extracting one or more regions to be observed; and integrating the plurality of captured images and generating an integrated image by an integration method determined based on a classification result of the classifying the one or more regions to be observed.