1. An opthalmological apparatus comprising: a first acquiring unit configured to acquire a reference AOSLO (Adaptive Optics Scanning Laser Ophthalmoscope) image and a reference WFSLO (Wide Field Scanning Laser Ophthalmoscope) image of an eye to be examined; a second acquiring unit configured to acquire a target AOSLO image and a target WFSLO image of the eye to be examined, and a processor configured to calculate a position of the target AOSLO image with respect to the reference AOSLO image, wherein, in a case where the position of the target AOSLO image with respect to the reference AOSLO image differs by more than a first threshold, the processor calculates a position of the target WFSLO image with respect to the reference WFSLO image, and the processor controls an AOSLO tracking mirror according to a difference in position of the target WFSLO image with respect to the reference WFSLO image.