HST/ACS F658N filter image, reproduced from Weis et al. (2004). The field of view is 1.5′× 1.5′. Several distinct features are identified with the terminology used by Walborn (1976). The main filter transmission is between λ6549−6623 Å, ranging over 3000 km s^-1 in velocity space. Eta Car’s outer ejecta have a large range of velocities and thus [N ii] λλ6548, 6583 and Hα emission contribute to the features observed here.