MACS 0416 colour image showing a 24″×24″ region centred on the Warhol arc. Other prominent caustic crossing galaxies where microlensing transients have been identified are also marked. The colour image was created by combining filters from two instruments: NIRCam (F444W and F356W for the red channel; F277W, F200W, and F150W for the green channel; F115W and F090W for the blue channel) and WFC3 (F814W, F606W, and F435W for the blue channel). The yellow square outlines the central region analysed in this study.