Optical and electrical performance comparisons between high power LED and HMI studio lighting including the engineering economics analysis

Abstract

A superior alternative to the conventional hydrargyrum medium-arc iodide (HMI) luminaires, high power light emitting diode (HP-LED) luminaires are increasingly being utilized in numerous modern lighting designs and applications. Specifically, this research is concerned with the comparative optical and electrical performance and engineering economic analysis of Fresnel-type HMI and HP-LED luminaires for studio lighting applications in the experiments conducted in a real studio environment. The findings revealed that, optically, the Correlated color temperature, luminous flux, luminous intensity and illuminance of the experimental HP-LED and HMI luminaires were comparable. The Color rendering index of the HP-LED was higher and its beam/spread output was more controllable. In the electrical aspect, the results showed that the HP-LED luminaire required significantly less power while producing lower %THD_v and %THD_i vis-à-vis the HMI counterpart. The payback period for the replacement of HP-LED luminaires was around 7 years and 7 months, which was shorter than the project life of 15 years. The commercial prospect of HP-LED luminaires is thus brighter as an excellent substitute for the conventional HMI luminaires in myriad applications, particularly in studio lighting for photography, cinematography, and broadcasting.

Keywords:

• Optical performance
• electrical performance
• engineering economics
• high power LED
• HMI studio lighting

Acknowledgment

The authors are deeply indebted to King Mongkut’s Institute of Technology Ladkrabang (KMITL)’s Energy System and Illumination Engineering Research Center (ESIRC) and to Technology Rajamangala University of Technology Thanyaburi (RMUTT)’s Faculty of Mass Communication for valuable assistance and suggestions. Sincere appreciation also goes to Shell Thailand for a financial sponsorship under the Shell Centennial Education Fund; and to DSE Co., Ltd. (Thailand) and Lek Lighting Equipment Co., Ltd. for instrument support.