We present a collection of 24 multiple object scenes recorded under 18 multiple light source illumination scenarios each. The illuminants are varying in dominant spectral colours, intensity and distance from the scene. We mainly address the realistic scenarios for evaluation of computational colour constancy algorithms, but also have aimed to make the data as general as possible for computational colour science and computer vision. Along with the images, we provide also spectral characteristics of the camera, light sources, and the objects and include pixel-by-pixel ground truth annotation of uniformly coloured object surfaces. The dataset is freely available at https://github.com/visillect/mls-dataset.