Comparative Analysis of DIALux evo and Relux in Lighting Design for Indoor Spaces

Abstract

The objective of this study is to compare the performance of DIALux evo 5.13.2.2 and ReluxDesktop 2025.1.9.0 in interior lighting design, evaluating their photometric accuracy, lighting distribution, usability, and compliance with lighting standards. The research followed an experimental simulation-based approach using an identical 3D model, the same surface reflectances, and the same photometric file in both programs; calculation parameters, workplane height, grid spacing, and interreflections were standardized to ensure comparability. The results indicate significant differences in average illuminance, uniformity, and spatial light distribution, with higher values reported by Relux and a more pronounced lateral variation observed in DIALux. Although both tools correctly interpreted the photometric data, neither fully met the requirements of NOM-025-STPS-2008 nor the recommendations of EN 12464-1:2021 in the evaluated scenario. The main limitation of this study is the absence of experimental validation and the lack of complete statistical analysis due to missing data from one simulation replica. However, the research provides an updated comparative assessment that highlights how differences in calculation engines can influence decision-making in lighting design projects. The study concludes that DIALux stands out for its accessibility and operational speed, whereas Relux offers greater normative stability and more consistent photometric values in interior environments, guiding users in selecting the most suitable software depending on project objectives and analytical needs.