Demonstration of the capabilities of D⁴PO based on a simulated but realistic data set gathered from a potential astrophysical high energy telescope. The spatial dimension is orientated vertically and the spectral/energy dimension horizontally. Point-like sources appear therefore as the horizontal lines. All fields are living over a regular grid of 350 × 350 pixels. Top panel: the assumed instrument’s exposure map, its Gaussian convolution kernel and the obtained data set, once on logarithmic scale and once the raw photon counts. For each photon count we obtain spectral and spatial information. The panels below display the diffuse, point-like, and background flux. For all signal fields we show the ground truth on the left hand side (), followed by its reconstruction (), the error () and the logarithmic uncertainty of the reconstruction (). For illustration purposes all fluxes are on logarithmic scale and clipped between −0.6 and 3.1, except the “Raw photon counts” () which are shown on their native scale.