Color rendering evaluation model for lighting of traditional Chinese freehand brushwork paintings in museums

Traditional Chinese freehand brushwork paintings displayed in museums require lighting sources with high color rendering accuracy. However, due to their unique visual characteristics—such as low saturation, broad halos, and an emphasis on tonal gradation—existing general-purpose color rendering evaluation methods are often inadequate. In this study, a full-scale (1:1) replica of a traditional Chinese painting exhibition hall was constructed in a laboratory. Sixty representative spectral power distributions (SPDs) were used as lighting conditions, and four representative paintings were selected for evaluation. A color fidelity assessment was conducted with 34 participants. Five principal spectral components were extracted from each SPD and correlated with the fidelity evaluations using a neural network algorithm. Based on this analysis, a targeted color rendering evaluation model for lighting in traditional Chinese freehand brushwork painting exhibitions was developed. This model predicts the fidelity presentation value of a light source, with a validated average relative error of 9.7%.