Comparison between the two different methods for generating velocity and dispersion fields for the [C II] emission line from the host galaxy of quasar P183+05. The top row shows the results from fitting a single Gaussian function to the spectrum of each individual spaxel. The data are masked to show only pixels that have been detected at >3σ in the total intensity field. The bottom row is the first moment of the data cube, where the data have been clipped at >1σ. Both methods yield roughly the same velocity and velocity dispersion field. Since the Gaussian fitting routine is independent of the S/N of the data, we opt to use this method in our analysis. The ALMA synthesized beam for these observations is shown in the inset in the lower left corner.