  Scanning transmission electron microscopy (STEM) has a broad range of
applications in materials characterization, including real-space imaging,
spectroscopy, and diffraction, at length scales from the micron to
sub-{\AA}ngstr\"om. The recent development and adoption of high-speed, direct
electron STEM detectors has enabled diffraction patterns to be collected at
each probe position, generating four-dimensional STEM (4D-STEM) datasets and
opening new imaging modalities. However, the limited pixel numbers in these
detectors enforce a tradeoff between angular resolution and maximum collection
angle. In this paper, we describe a straightforward method for quantifying
4D-STEM data by utilizing the full flux of the electron beam, including
electrons scattered beyond the limits of the detector. This enables
significantly increased experimental flexibility, including the synthesis of
quantitative, high-contrast complementary annular dark field (cADF) STEM images
from low-angle diffraction patterns whilst maintaining high angular resolution;
as well as the optimization of electron dose and the more effective use of low
dynamic range detectors.
