Reconstruction of the ground truth from the diffusion model for three mock galaxies from the MaNGIA test set. The first three columns display the input observable maps provided to the diffusion model: stellar mass, stellar velocity, and velocity dispersion. These maps have been forward-modeled through the MaNGIA pipeline and subsequently normalized to retain only gradient information. The fourth column shows the ground-truth 2D ex situ stellar mass fraction map from the TNG50 cosmological simulation. The fifth and sixth columns present two individual samples from the diffusion model. The seventh column displays the median prediction from 100 samples. Finally, the last two columns show the model uncertainty (computed as the 84th–16th percentile range) and the residual between the median prediction and the ground-truth map, respectively.