A standing wave interferometric microscope is disclosed herein. An example microscope may include an illuminator, for illuminating a specimen with a standing wave of input radiation at an analysis location to cause the specimen to fluoresce, the specimen arranged in the analysis location, a pair of projection systems, arranged at opposite sides of the analysis location, coupled to collect at least a portion of the fluorescence and direct a corresponding pair of fluorescence light beams into a respective pair of inputs of an optical combining element, a wavefront modifier for producing astigmatism in at least one of the fluorescence light beams entering the optical combining element, and a detector for examining output light from said combining element.