Field dominance defines whether a field type 1 or type 2 represents the start of a new interlaced TV frame. Usually it is field 1 but there is no fixed rule. Dominance may go unnoticed until flash fields occur at edits made on existing cuts. Replay dominance set the opposite way to the recording can cause a juddery image display. Much equipment, including Quantel’s, allows the selection of field dominance and can handle either.