A total station comprising - a base, - a support rotatably arranged on the base around a vertical axis, - an azimuthal angle encoder configured for measuring an azimuthal angle of the support, - a telescope rotatably arranged on the support around a horizontal axis, said telescope comprising - a laser unit configured for emitting a measuring beam along a beam axis, - a camera configured for capturing images with a field of view comprising the beam axis at least in part, - an elevative angle encoder configured for measuring an elevative angle of the telescope, and - a computer unit, wherein the computer unit is configured for - receiving from the camera a first image captured in a first face and a second image captured in a second face, wherein in the second face the camera is rotated around the optical axis by between 170° and 190° compared to the first face, and wherein the fields of view of the camera in the first face and in the second face overlap at least in part, - receiving from the respective angle encoder(s) at least one of an azimuthal angle pair and an elevative angle pair, said azimuthal angle pair comprising a first azimuthal angle in a first face and a second azimuthal angle in a second face, and said elevative angle pair comprising a first elevative angle in the first face and a second elevative angle in the second face, - matching the first image and the second image with a relative rotation and a relative translation, - determining the relative rotation of the matched first image and second image, - determining the relative translation of the matched first image and second image, - based on the respective angle pair(s), the relative rotation, the relative translation, determining an instrument error comprising at least one of - a horizontal collimation error, - a vertical index error, - based on the instrument error, applying an angle offset to each reading of the respective angle encoder(s). - a base, - a support rotatably arranged on the base around a vertical axis, - an azimuthal angle encoder configured for measuring an azimuthal angle of the support, - a telescope rotatably arranged on the support around a horizontal axis, said telescope comprising - a laser unit configured for emitting a measuring beam along a beam axis, - a camera configured for capturing images with a field of view comprising the beam axis at least in part, - a laser unit configured for emitting a measuring beam along a beam axis, - a camera configured for capturing images with a field of view comprising the beam axis at least in part, - an elevative angle encoder configured for measuring an elevative angle of the telescope, and - a computer unit, wherein the computer unit is configured for - receiving from the camera a first image captured in a first face and a second image captured in a second face, wherein in the second face the camera is rotated around the optical axis by between 170° and 190° compared to the first face, and wherein the fields of view of the camera in the first face and in the second face overlap at least in part, - receiving from the respective angle encoder(s) at least one of an azimuthal angle pair and an elevative angle pair, said azimuthal angle pair comprising a first azimuthal angle in a first face and a second azimuthal angle in a second face, and said elevative angle pair comprising a first elevative angle in the first face and a second elevative angle in the second face, - matching the first image and the second image with a relative rotation and a relative translation, - determining the relative rotation of the matched first image and second image, - determining the relative translation of the matched first image and second image, - based on the respective angle pair(s), the relative rotation, the relative translation, determining an instrument error comprising at least one of - a horizontal collimation error, - a vertical index error, - based on the instrument error, applying an angle offset to each reading of the respective angle encoder(s). - receiving from the camera a first image captured in a first face and a second image captured in a second face, wherein in the second face the camera is rotated around the optical axis by between 170° and 190° compared to the first face, and wherein the fields of view of the camera in the first face and in the second face overlap at least in part, - receiving from the respective angle encoder(s) at least one of an azimuthal angle pair and an elevative angle pair, said azimuthal angle pair comprising a first azimuthal angle in a first face and a second azimuthal angle in a second face, and said elevative angle pair comprising a first elevative angle in the first face and a second elevative angle in the second face, - matching the first image and the second image with a relative rotation and a relative translation, - determining the relative rotation of the matched first image and second image, - determining the relative translation of the matched first image and second image, - based on the respective angle pair(s), the relative rotation, the relative translation, determining an instrument error comprising at least one of - a horizontal collimation error, - a vertical index error, - a horizontal collimation error, - a vertical index error, - based on the instrument error, applying an angle offset to each reading of the respective angle encoder(s).