  Local amplitude aberrations caused by scintillation can impact the
reconstruction process of a wavefront sensor (WFS) by inducing a spatially
non-uniform intensity at the pupil plane. This effect is especially relevant
for the commonly-used Shack-Hartmann WFS (SHWFS), which can lose slope
information for portions of the beam where the signal is faint, leading to
reduced reconstruction performance and eventually total failure as the level of
scintillation increases. An alternative WFS is needed for such conditions. The
nonlinear curvature wavefront sensor (nlCWFS) has been shown to achieve better
sensitivity compared to the SHWFS under low light levels. Additionally, the
nlCWFS has demonstrated the ability to maintain its sensitivity in the presence
of scintillation, using amplitude aberrations to help inform the reconstruction
process, rather than hinder. Experiments to date have thus far only shown
reconstruction results for a single scintillation value. Building upon previous
simulations and laboratory experiments, we have built a testbed to quantify the
effects of varying scintillation strength on the wavefront reconstruction
performance of the nlCWFS compared to an equivalent SHWFS. In this paper, we
present results showing the difference in performance between the nlCWFS and
SHWFS as a function of relative flux and scintillation strength.
