What two specific types of shape distortion are identified in imaging practices?

In imaging practices, the two types of shape distortion specifically identified are elongation and foreshortening. Elongation occurs when an object appears longer than it actually is due to the angle of projection or the position of the imaging receptor. This can happen, for instance, if the object is not parallel to the imaging receptor.

Foreshortening, on the other hand, is when an object appears shorter than its actual length. This can occur when the object is angled in a way that affects the perception of its dimensions on the image. Both elongation and foreshortening are critical to understand, as they can heavily influence diagnosis and the overall assessment of the images produced in various imaging modalities.

The other options do not accurately represent the specific types of shape distortion recognized in imaging. Magnification, although related to size distortion, does not address shape distortion directly and can manifest without impacting the actual shape of objects.