The "polarization 3D system" has been the standard for theatrical presentations since it was used for "Bwana Devil" in 1952, though early Imax presentations were done using the eclipse system and in the 1960s and 1970s classic 3D films were sometimes converted to anaglyph for special presentations. The polarization system has better color fidelity and less ghosting than the anaglyph system. In the post-'50s era, anaglyph has been used instead of polarization in feature presentations where only part of the film is in 3D such as in the 3D segment of ' and the 3D segments of '.