  The presence of off-axis tilt and Petzval curvature, two of the lowest-order
off-axis Seidel aberrations, is shown to improve the Fisher information of
two-point separation estimation in an incoherent imaging system compared to an
aberration-free system. Our results show that the practical localization
advantages of modal imaging techniques within the field of quantum-inspired
superresolution can be achieved with direct imaging measurement schemes alone.
