Image of the $9\stackrel{\prime }{.}1\times 9\stackrel{\prime }{.}1(2$ Mpc × 2 Mpc, approximately 0.5 R₂₀₀ of the cluster) region around A 2390. The image is a combination of an RGB image of the PSF-subtracted NISP images and a J_E+H_E black and white background. Cluster members are colour-coded according to whether their redshift is spectroscopic (red circles) or photometric (teal squares). North is up, and east is to the left. This image highlights the importance of removing bright stars close to the cluster centre to study the diffuse light (see Sect. 3.1).