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This is artificial, and an underestimate of the true uncertainty, as we\n-        // ought to be marginalizing over the difference between the fluxes - but that integral would\n-        // often diverge if we don't take into account the constraints, and if we do, the probability\n-        // distribution we get is complicated (Gaussian times a difference of error functions) and\n-        // asymmetric, so we'll leave that as a potential project for the future.\n-        result.fluxSigma = expData.fitSysToMeasSys.flux / std::sqrt(p_hessian_pt(1,1));\n+        // To compute the error on the flux, we treat the best-fit composite profile as a continuous\n+        // aperture and compute the uncertainty on that aperture flux.\n+        // That means this is an underestimate of the true uncertainty, but it's the sort that kind of\n+        // makes sense for colors, and it's consistent with the fact that we're also ignoring 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