Comparison of the LFAH2 (left panels) and LFAV2 (right panels) pixels with and without spline baseline correction. Dark blue lines show the average spectrum over 84 spectra. Lower panels: residual between the H and V data with and without spline correction. There is a 5 kelvin difference between the peak intensity before and after spline correction, indicating that spline correction has not affected the line intensity. LFAH2 and LFAV2 are not coaligned and are offset onthe sky by 2 arcseconds, which might account for the different line intensity.