GTC OSIRIS narrowband transit light curves at (top-to-bottom) 8839, 7665, 7582, and 6792 Å, with an arbitrary flux offset applied to each curve for clarity. The best-fit models are also over-plotted, along with the residuals (bottom four curves), which have a y-axis error bar corresponding to the per-point flux uncertainty. The light curves are near-Poisson limited, with per-point S/N levels between 1149 and 1351.