These calibration files are used to register the 4 channels of the microscope to each other laterally as well as map the localization axial positions based on their fitted widths.

'lateral-registration' contains the following files:
2019_01_28_REG2.tif: raw (dense) bead images as the focus is stepped roughly from the lowest focal plane of the multi-plane/-channel microscope through to roughly the top focal plane.
2019_01_28_REG2.sf: shiftfield map, readable by the python-microscopy environment.


'psf' contains the following files:
2019_01_28_PSF1.tif: raw (sparse) bead images as the microscope foci are stepped through the bead sample.
2019_01_28_PSF1_bead_conv.am: astigmatism map file used by the python-microscopy environment to map the z position of localizations using their fitted widths. The size of the beads (99 nm) is accounted for in the bead-convolved Gaussian model function used in fitting.

