  We examine the interplay between spectral bandwidth and illumination
curvature in ptychography. By tailoring the divergence of the illumination,
broader spectral bandwidths can be tolerated without requiring algorithmic
modifications to the forward model. In particular, a strong wavefront curvature
transitions a far-field diffreaction geometry to an effectively near-field one,
which is lees affected by temporal coherence effects. The relaxed temporal
coherence requirements allow for leveraging wider spectral bandwidths and
larger illumination spots. Our findings open up new avenues towards utilizing
pink and broadband beams for increased flux and throughput at both synchrotron
facilities and lab-scale beamlines.
