Fig. 8
From: Detection of cavities in a salt mine with cosmic muons: expected results and first data
Example of applying a filter to reduce statistical fluctuations and improve cavity image quality. Left: no filter applied. Middle: application of a median filter \(3 \times 3\). Right: RTN bins in the middle figure with values \(<0\) are set to zero to improve image contrast. All histograms have a bin size of \(4^\circ \times 4^\circ\) and the same data acquisiton time of 60 days.
