The identity w−1=−2/(z+1) gives ∣w−1∣=2/r on ∣z+1∣=r. Thus the imagecircle has center one and radius2/r. Points strictly inside the original circle satisfy ∣w−1∣>2/r; the center itself maps to infinity. The interior therefore becomes the exterior together with infinity on the Riemann sphere, rather than the interior of the imagecircle. This inversion is auseful warning against assuming conformality preserves global inside/outside assignments.