1. A method for shimming a magnetic field in a magnetic resonance tomography (MRT) device, the method comprising: determining a field of view for an object under examination; automatically adapting the field of view for the object under examination to an area of the object under examination to be examined by the MRT device; performing an adjustment measurement of the magnetic field before the MRT device records an image, a field map of the field of view for the object under examination being defined based on the adjustment measurement; and shimming the magnetic field for the field of view for the object under examination based on the field map of the field of view for the object under examination.