A method, performed by a system, for optimizing a set of matched features, the method comprising the following steps performed by the system: a) matching features between an optical image and a geo-referenced orthoimage to produce an initial set of N matched features, each matched feature having a respective matched feature location in the optical image; b) determining an initial position solution corresponding to the optical image using the initial set of N matched features; c) determining a set of N sub-solutions, wherein each of the N sub-solutions is a position solution using a different set of N-1 matched features, wherein each set of N-1 matched features is the initial set of N matched features having a different matched feature excluded therefrom; d) calculating a Z-score for each sub-solution in the set of N sub-solutions using the set of N sub-solutions as the population for the Z-score; e) calculating a residual for each sub-solution in the set of N sub-solutions having a Z-score above a Z-threshold, wherein each residual is based on a distance between the matched feature location of each matched feature in the optical image and a predicted location of that matched feature according to a respective sub-solution for that residual; if any of the residuals are less than a residual threshold, f) excluding a matched feature corresponding to the sub-solution for that residual from the set of N matched features to produce an optimized set of matched features, wherein the matched feature corresponding to the sub-solution is the matched feature that was excluded from the set of N matched features when determining that sub-solution; and g) determining a refined position solution corresponding to the optical image using the optimized set of matched features. a) matching features between an optical image and a geo-referenced orthoimage to produce an initial set of N matched features, each matched feature having a respective matched feature location in the optical image; b) determining an initial position solution corresponding to the optical image using the initial set of N matched features; c) determining a set of N sub-solutions, wherein each of the N sub-solutions is a position solution using a different set of N-1 matched features, wherein each set of N-1 matched features is the initial set of N matched features having a different matched feature excluded therefrom; d) calculating a Z-score for each sub-solution in the set of N sub-solutions using the set of N sub-solutions as the population for the Z-score; e) calculating a residual for each sub-solution in the set of N sub-solutions having a Z-score above a Z-threshold, wherein each residual is based on a distance between the matched feature location of each matched feature in the optical image and a predicted location of that matched feature according to a respective sub-solution for that residual; if any of the residuals are less than a residual threshold, f) excluding a matched feature corresponding to the sub-solution for that residual from the set of N matched features to produce an optimized set of matched features, wherein the matched feature corresponding to the sub-solution is the matched feature that was excluded from the set of N matched features when determining that sub-solution; and g) determining a refined position solution corresponding to the optical image using the optimized set of matched features.