  Fluorescence fluctuations-based super-resolution microscopy (FF-SRM) is an
emerging field promising low-cost and live-cell compatible imaging beyond the
resolution of conventional optical microscopy. A comprehensive overview on how
the nature of fluctuations, label density, out-of-focus light, sub-cellular
dynamics, and the sample itself influence the reconstruction in FF-SRM is
crucial to design appropriate biological experiments. We have experimentally
compared several of the recently developed FF-SRM techniques (namely ESI,
bSOFI, SRRF, SACD, MUSICAL and HAWK) on widefield fluorescence image sequences
of a diverse set of samples (namely liposomes, tissues, fixed and living
cells), and on three-dimensional simulated data where the ground truth is
available. The simulated microscopy data showed that the different techniques
have different requirements for signal fluctuation to achieve their optimal
performance. While different levels of signal fluctuations had little effect on
the SRRF, ESI and SACD images, image reconstructions from both bSOFI and
MUSICAL displayed a substantial improvement in their noise rejection,
z-sectioning, and overall super-resolution capabilities.
