Without exception, primaries are the only events that are ever migrated. Arranging for a more complete set of primaries will enhance imaging. The approximate image of an unrecorded primary can be realized by isolating and migrating a subevent primary of a multiple. A more complete set of images of primaries, consisting of recorded primaries and (approximated) unrecorded primaries, can enhance imaging. Multiples are not and cannot be migrated, and care must be taken for creating inevitably false events in this method, called cross talk.