An example of using the Snellen et al. (2008) method to analyze the sodium D1 line in the WASP-69b data set. The panels represent (from top to bottom) passbands of 0.075, 0.15, and 0.3 nm, and the magenta points correspond to the data while the black line corresponds to a model light curve generated using the methods of Mandel & Agol (2002). We do not detect any signal in any of the three passbands.