Difference between the predicted and the input parameters from top to bottom: log(Age), [M/H] and E(B-V) for the sample limited to i < 19.5, divided into different SSP synthetic photometry (from left to right: E-MILES, CB19, and XSL). The colour intensity corresponds to the ‘observed’ magnitude. Red points indicate the median values in bins, with red error bars showing the interquartile range (25th to 75th percentiles) of the distribution.