High-pass filtering of a 2D radio relic model in the presence of SZ decrement, done as a simplified exercise for interferometric observation. The inset panels show the input image before (left) and after (right) filtering, using the same color scale. The multiple curves in the main panel plot represent the profiles for synchrotron-only model (blue solid line), filtered synchrotron model (blue dotted line), synchrotron+SZ model (red dashed line), and filtered synchrotron+SZ model (black solid line). We see that the high-pass filter effectively removes the large-scale SZ signal from the image, while keeping the measured peak flux close to the input (unfiltered) value of the synchrotron+SZ model, and not the “synchrotron only” model.