Figure 1386 shows the mass-thickness effects on both EDS and EELS signals (or intensities). Both signals increases with the mass-thickness factor (f) when the factor f is smaller than f_ms1, while the the EELS signal decreases rapidly when f is greater than f_ms1. On the other hand, the EELS signal becomes smaller than EDS signal when f is greater than f_ms2. Therefore, the EDS and EELS signals will be reversed between the cases of f < f_ms1 and f >f_ms2. That is, in the case of f >f_ms2, higher concentration of an specific element probably does not provide high intensity or contrast in EELS measurements, but it does for EDS.