When RT Image Plane (3002,000C) is NORMAL and RT Image Orientation (3002,0010) is not provided, the orientation is defined as follows: The image viewing direction shall be from the radiation source to the image (i.e., in the sense of a beam's eye view, or along the negative Zr direction of the IEC X-RAY IMAGE RECEPTOR coordinate system).

If RT Image Plane is NON_NORMAL, any rotation defined by RT Image Orientation is performed about the origin of the IEC X-RAY IMAGE RECEPTOR coordinate system. The definitions of the x and y coordinates of the RT Image Position (3002,0012) are defined before any rotation of the image plane is taken into account, see Figure C.8.8.2.7-1.

The direction of rows shall be along the positive Xr direction and the direction of the columns shall be along the negative Yr direction of the IEC X-RAY IMAGE RECEPTOR coordinate system.