SVĚTLO 2012/2EN25measurements and calculationsIntroductionA lighting model which enables ver-ification and improvement of calcula-tions and simultaneously enables us to test different alternatives of technical de-signs for individual parts of the lighting system is an important criterion when evaluating lighting system quality. An intense expansion in the field of lighting programs has enabled the development of tools capable of complex designs and parameter calculation in lighting sys-tems which take light effects created by artificial lighting and natural light into account. They can generate the bright-ness, colour and structure of 3D space very realistically.Simulation is a convenient tool for en-hancement of the design, calculation and modelling process. This can be helpful in eliminating various problems, e.g. when eliminating unnecessary over-design of the lighting system’s elements or the bad design of particular parts of the system, it also enables a visual review of the quali-ty and esthetics of the design without the need to employ expensive physical mod-els. The selection and utilization of suit-able software affects the project heavily. A selection of unsuitable software means that the whole simulation becomes inef-fective.Material and methodsThis paper is concerned with compar-ing the DIALux and Relux software bun-dles used for lighting system simulation. The comparison was based on evaluating the visualization output of settings and technical calculations.These lighting software products, de-pending upon their configuration, ena-ble through their graphic interface and input parameters of the object being re-Comparison of the software programs for lighting simulation – DIALux and ReluxIng. Richard Hnilica, PhD., Ing. Michal Krak, Ing. Miroslav Dado, PhD.*)*) All authors – Department of Manufacturing Technology and Materials, FEVT, TU in ZvolenFig. 2. Layout with the main internal elements of the workspace (1, 2, 3 – rectangular column; 4 – tech-nological equipment; 5, 6, 7 – stage; 8, 9 – door; 10, 11, 12, 13, 14 - window)Fig. 1. The trend searching the words DIALux and Relux through the service Insights for Search beta by GoogleDIALuxReluxThe selection and correct use of simulation software considerably affects the whole project. If an unsuitable program is chosen the simulation could be ineffective. This is why deciding which program to use is so difficult. This paper tries to clarify the work procedures and lighting evaluation system in the DIALux and Relux programs.