1. An ophthalmologic photographing apparatus comprising: a photographing optical system including an optical scanner configured to scan an examinee's eye with measurement light and a detector configured to detect a coherent state of reflected, light of the measurement light from the examinee's eye and reference fight, the photographing optical system being configured to capture a tomographic image of the examinee's eye in response to an output signal from the detector; a reference data setting unit configured to set a photographing condition of a previously acquired captured image as reference data for a follow-up; an image capture data setting unit configured to set the reference data set by the reference data setting unit as image capture data for the follow-up; and a tomographic image acquisition controller configured to acquire a tomographic image of the examinee's eye by controlling the photographing optical system based on the reference data set as the image capture data.