Due to fluctuating properties, high proportions of alternative fuels : Are a major challenge for multi-fuel burners used in industrial combustion processes. This article presents a new, camera-based measurement system that allows the online extraction of parameters concerning the flight and, hence, combustion behavior [ of the fuel. Based on these parameters, the combustion process can be analyzed and optimized, thus ensuring consistent product quality despite high proportions of alternative fuels. © 2019 Bauverlag BV GmbH. All rights reserved.