Impact of the sensitivity of the MUSE spectrum on our ability to constrain the age and metallicity of single-burst models of ID53. We simulated a single-burst model with [Z/H]=-2.15 and log₁₀(age/yr) = 6.5 (illustrated with the dotted line) and derived the likelihood distribution with four different sensitivities. These correspond to exposure times of 10 h (red), 30 h (green), 140 h (blue; i.e. these data), and 140 h on a telescope that is five times larger (i.e. an MXDF on the ELT).