Data processing was carried out using the Pyxem open-source Python library for multidimensional diffraction microscopy. Calibration data were recorded from standard MoO3 and Au-cross-grating samples as reported previously. Briefly, the rotation between the scan direction and the diffraction pattern was calibrated by identifying the angle between the characteristic long axis of MoO3 crystals of known habit and the corresponding diffraction spots. An Au cross-grating with a 500 nm period was used to calibrate the image pixel size. By recording an SED dataset from polycrystalline Au, a diffraction pattern consisting of characteristic rings was acquired and fitted to a set of ellipses to determine residual elliptical distortions and to determine the diffraction camera calibration. For long chain hydrocarbon samples, the direct beam was first aligned to pixel precision and then centered using a crosscorrelation function in Pyxem to subpixel precision. An affine transformation matrix was used to remove the measured elliptical distortions and the pattern rotation relative to the scan direction.