Local activation times (LATs) are mapped by computing an LAT range for a plurality of electrophysiology data points, splitting the LAT range into two or more LAT sub-ranges, splitting the LAT map into a corresponding number of LAT sub-maps, and associating a mapping sub-convention (e.g., a color spectrum, grayscale, and/or pattern density range) with each of the LAT sub-maps. The mapping sub-conventions can be scaled (e.g., linearly, logarithmically) to their respective LAT sub-ranges, allowing for an overall LAT map that offers increased granularity over LAT sub-ranges of particular interest to the practitioner. The LAT sub-maps can be updated in real time as additional electrophysiology data points are collected.