A method for examining a specimen using a microscope, in particular a confocal scanning microscope, has the following steps. First, a scanning region, containing a specimen to be examined or a plurality of specimens to be examined, in a predeterminable spatial direction is selected. Then, a series of images in the scanning region along the spatial direction are recorded such that the individual images can be uniquely assigned to individual planes in the spatial direction. Then, an image analysis method is selected with at least one predeterminable criterion with respect to the specimen to be examined or the specimens to be examined. Finally, the image analysis method is applied to the individual planes for ascertaining a preferred plane which at least to a great extent satisfies the predeterminable criterion or criteria. Furthermore, a microscope for carrying out the method is specified.