Active control of street light sources based on sensor data is desired to meet requirements on traffic safety and environmental protection. In this report, we summarise the results of a research study focusing on some of the fundamental problems occurring when performing real-world sensor measurements for lighting control. In particular, we present results on the impact of traffic and the relationship between sensor angle and measured road surface luminance. Moreover, we present a comparison between different approaches to estimating the veiling luminance in tunnel lighting applications.