Results of SED fitting tests using simple mock SEDs generated with FSPS. Three sets of mock SEDs are made: G + L + E, L + E, and E, and the results of fitting on them are shown in the top, middle, and bottom rows, respectively. We also fit the mock data with and without applying the mass-age and mass-Z priors and the results are shown in blue and red colours, respectively. The histograms in the insets show ratios (in logarithmic scale) between the best-fit and true values.