Earthquake surface deformation provides key constraints on the geometry, kinematics, displacements, and complexity of fault rupture. However, deriving these precise characteristics from past earthquakes is complicated by a lack of detailed knowledge of landforms before the earthquake and how the landform has since been modified. The 1987 M_w 6.6 Edgecumbe earthquake in the northern Taupō volcanic zone in New Zealand represents a moderate-magnitude earthquake with complicated surface rupture that occurred before widespread high-resolution topographic data were available. We use historical aerial photos to build pre- and post-earthquake digital surface models using structure-from-motion techniques. By differencing the two surface models, we more definitively measure discrete and distributed deformation from this earthquake and compare the effectiveness of the technique to traditional field- and lidar-based studies. We identified most fault traces recognized by field mapping in 1987, mapped new traces not recorded in the field, and take denser, detailed remote slip measurements with a vertical separation resolution of ~0.3 m. Our maximum and average vertical separation measurements on the Edgecumbe fault trace (2.5 ± 0.3 m and 1.2 m, respectively), are similar to field-based maximum and recalculated averages of 2.4 m and 1.1 m, respectively. Importantly, this technique is able to discern between new fault scarps and pre-existing fault scarps better than field techniques or lidar-based measurements alone. Results from this approach can be used to refine estimated subsurface fault geometries and slip distributions at depth, and here is used to investigate potential magmatic-tectonic stress trigging in the northern Taupō volcanic zone.