A device comprising an image data correction device and an ionizing radiation detection device, wherein the ionizing radiation detection device is configured to detect ionizing radiation in a plurality of energy ranges transmitted through an object to which radiation is irradiated from a radiation source, the radiation detection device comprising: a first detector (D,LE,HE,E1,E2,En) for detecting ionizing radiation in a first energy range that is transmitted through the object to generate first radiation image data; at least a second detector (D,LE,HE,E1,E2,En) configured in parallel to and side by side the first detector with a gap (Z_GAP, Z_GAP 1, Z_GAP m) sandwiched between the first and the second detectors, for detecting ionizing radiation in a second energy range that is transmitted through the object to generate second radiation image data, wherein the first and the second energy ranges are different; the first and the second detectors are configured to receive the ionizing radiation concurrently so that the first and the second image data are generated and sampled concurrently; characterised in that the image data correction device comprises; at least one processor, and at least one memory storing program instructions (1106,1108) that, when executed by the at least one processor, cause the device to: digitally determine a correction value (Z corr, Z corr_m) for the second radiation image data based on a width (Z_GAP, Z_GAP 1, Z_GAP m) of the gap and a pixel pitch so that a dimensional sampling is equal to the pixel pitch, wherein the width of the gap is less than the pixel pitch and the correction value is configured to the correction of images for geometrical aspects. a first detector (D,LE,HE,E1,E2,En) for detecting ionizing radiation in a first energy range that is transmitted through the object to generate first radiation image data; at least a second detector (D,LE,HE,E1,E2,En) configured in parallel to and side by side the first detector with a gap (Z_GAP, Z_GAP 1, Z_GAP m) sandwiched between the first and the second detectors, for detecting ionizing radiation in a second energy range that is transmitted through the object to generate second radiation image data, wherein the first and the second energy ranges are different; the first and the second detectors are configured to receive the ionizing radiation concurrently so that the first and the second image data are generated and sampled concurrently; characterised in that the image data correction device comprises; at least one processor, and at least one memory storing program instructions (1106,1108) that, when executed by the at least one processor, cause the device to: digitally determine a correction value (Z corr, Z corr_m) for the second radiation image data based on a width (Z_GAP, Z_GAP 1, Z_GAP m) of the gap and a pixel pitch so that a dimensional sampling is equal to the pixel pitch, wherein the width of the gap is less than the pixel pitch and the correction value is configured to the correction of images for geometrical aspects. at least one processor, and at least one memory storing program instructions (1106,1108) that, when executed by the at least one processor, cause the device to: digitally determine a correction value (Z corr, Z corr_m) for the second radiation image data based on a width (Z_GAP, Z_GAP 1, Z_GAP m) of the gap and a pixel pitch so that a dimensional sampling is equal to the pixel pitch, wherein the width of the gap is less than the pixel pitch and the correction value is configured to the correction of images for geometrical aspects.