Impact of the availability and precision of the measurement of the intrinsic Hα luminosity on our ability to constrain the age and metallicity of single-burst models of ID53. We simulated a single burst model with [Z/H]=-1.15 and log₁₀(age/yr) = 6.5 and derived the likelihood distribution allowing all Hα luminosities, or only those models that are within 25 and 10 % of the real Hα luminosity of the model.