As independent measuring system TRITOP can be used as optical cmm which combines the classical approach of a tactile measuring machine with the advantages of the optical measuring technology. For this the features to be measured are signalled by reference markers or special adaptors to be calculated later automatically by the software. The alignment to the tool coordinate system occurs about marked RPS points, so that no more special measuring fixtures or adjustment on the measuring table is necessary any more. This approach and the high mobility permit the quick and efficient measurement directly on the object in the production surroundings.