Image registration based on the relative position of an imager to an imaged object

The invention provides system and method for image composition. A first image of an object (130) is acquired using an imager (110, 230) (910), first positional information for the imager (110, 230) with respect to the object (130) (920) is obtained. A second image of the object (130) is acquired using the imager (930) and second positional information for the imager (110, 230) with respect to the object (130) (940) is obtained. A composed image is obtained using the first and second images. A spatial relationship between the images is maintained using the positional information to register the images. A composed image may be created by constructing a memory map (310) of image data (320) related to the object (130) and inserting the images into the memory map (310) based on the positional information, for example. A subtraction mask may also be generated to show differences between the images, for example during angiographic imaging and positioning feedback for the imager may also be provided based on the positional data.