PyMieScatt computation time for the extinction coefficient of a Titan tholin spherical particle vs. the particle size. For each particle size, the Q_ext are computed on the full wavelength grid of the optical constants (see Sect. 2.1). The green and red lines represent the run time of a model with PYMIESCATT with one and four cloud species, respectively. The time displayed are the median times for ten iterations to avoid outliers. The dashed blue line is the average model time for a cloud-free TAUREX forward model with 100 layers (Al-Refaie et al. 2021).