CXR’s can be misleading, some common points to be aware of:
Erect vs supine (fluid layering):
AP view can magnify the heart (PA vs AP):
Rotation – are the spinous processes centered between the medial edges of the clavicles? Note how heart width changes with rotation.
Penetration – vertebral bodies should be just visible behind the heart
Inspiration – should be about 9-10 posterior ribs seen