Illustration of alternative IMF parameterisations used in the stellar population modelling. The standard Salpeter IMF is shown in orange. Solid black and grey lines represent bimodal IMFs with logarithmic slopes of 1.3 and 3.0, respectively. Dotted versions of these lines modify the low-mass slope below 0.2 M⊙ to 0.3, mimicking the Kroupa IMF in that regime. The dashed red line corresponds to a bimodal IMF (slope = 3.0) with a reduced turning point mass range of 0.4–0.6 M⊙. Finally, the solid orange line also doubles as a unimodal IMF with slope = 1.3 for comparison.