Fig. 11 in Micro-computed tomography for natural history specimens: a handbook of best practice protocols

Fig. 11. Histogram of the grayscale value frequency of the scanned specimen (bivalve Musculus costulatus (Risso, 1826). Each peak represents a different structure (in terms of density) of the scanned bivalve. Bright grayscale values (representing low densities) are located at the left side of the histogram, darker values (representing high values) at the right side of the histogram. A. The selection of a range including all peaks, reveals the more detailed morphology of the bivalve (both soft/low density and hard/high density structures). B. A restricted range of histogram values removes structures with brighter values (= low densities). C. A restricted range of histogram values including only one peak reveals only the darkest values (= most dense structures) of the bivalve which correspond to the shell. Image by HCMR micro-CT lab.