An X-ray apparatus for image acquisition and a related method. The apparatus comprises a field-of-view corrector (CS) configured to receive a scout image (SI) acquired by the imager with a tentative collimator setting in a pre-shot imaging phase where said imager operates with a low dosage radiation cone causing the detector to register the scout image. The low dosage cone has, in the detectors image plane, a first cross section smaller than the total area of the detector surface. The field-of-view corrector (CS) uses said scout image to establish field-of-view correction information for a subsequent imaging phase where the imager is to operate with a high dosage radiation cone, the high dosage higher than the low dosage.