Transmission light curves from HARPS observations of HD 189733b, for three different bandwidths: 0.75 Å (left column), 1.5 Å (middle column), and 3.0 Å (right column). Only nights 1 and 3 are used here. First row: final observed transmission light curve of the Na I D lines from our data reduction. The relative flux of D1 and D2 lines is averaged and binned with a 0.002 phase step (black line). The red line is the modeled transmission light curve, which is the combination of the best-fit Na I absorption and the CLV effect (Yan et al. 2017). This model is calculated theoretically and there is no fitting to the actual data. Second row: the CLV effect. The black line is the result of removing the Na I absorption model from the observed transmission light curve. The modeled CLV effect is shown in red. Third row: the Na I absorption light curve obtained dividing the observed transmission light curve by the modeled CLV effect (black line). The red line is the best-fit Na I absorption model. Forth row: residuals between the observed transmission light curve and the model. The errorbars represent the photon noise within the passband.