Sample correlations between the intensity gradients along (top) or across (bottom) the SPICE slit with the velocity derived from line fitting. The verticle dashed lines represent the ±1σ range that was excluded from the linear fit (solid line). This sample was taken from the C III raster taken between 13:15:36 and 13:20:57 UT. The strong blueshift from the erupting filament is clearly visible between the dashed lines.