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Dramatic differences in the elastic scattering of the neutron rich nuclei He 6 and He 8 are found when new high quality data for the He 8+ Pb 208 system are compared with previously published He 6+ Pb 208 data at the same laboratory frame incident energy. The new He 8 data are of the same level of detail as for stable beams. When comparing them with those previously obtained for He 6+ Pb 208 at the same energy, it is possible to determine from the data alone that He 6 has a much longer range absorption than He 8. However, both nuclei show significant absorption beyond their strong absorption radii. While it has been known for a long time that elastic scattering at energies around the barrier only determines the optical potential over a small distance in radial space, typically±0.5 fm or so, both the He 6 and the He 8 imaginary potentials obtained from various optical model fits to these data are the same over a …