The fit of the PSF along the axial dimension does not take into account potential tilt of the PSF. Thus, for tilted PSFs, the value of the Z FWHM will be an under-estimate. The effect won't be huge but we ideally should be finding the axis of the PSF and fitting along that.
The fit of the PSF along the axial dimension does not take into account potential tilt of the PSF. Thus, for tilted PSFs, the value of the Z FWHM will be an under-estimate. The effect won't be huge but we ideally should be finding the axis of the PSF and fitting along that.