Chromatic dependence of (F_fit − F_truth)/F_truth for stars with 19 < m_truth < 21.5. Small black points are individual measurements. Larger red points are the data binned every 0.05 mag, with the position of the red point at the mean of of J129_fit − H158_fit in that bin. The fit slope of the red points between −0.15 < J129_fit − H158_fit < 0.15 with its associated error is reported as s_color in the upper-left corner for each panel.