Determination of stellar age through isochrone fitting for cases with and without spectroscopic constraints. The grey dotted line on each panel shows the equality relation (y = x). Left: Logarithm of age (log(τ)). Uncertainties from each approach are shown with different colours for easier comparison. Centre: Uncertainties in age Δlog(τ) defined as 16th-to-84th percentile or ±1σ ranges. Right: Comparison of best-fitting initial metallicities [Fe/H]_init.