Equivalent widths of the 5780 and 5797 DIBs correlated with column densities of CH (top panels) and CH⁺ (bottom). Closer relations are emphasized with the fitted straight lines. 5797 DIB is more closely correlated with N(CH), while 5780 DIB with N(CH⁺) with correlation coefficients equal to 0.89 and 0.72, respectively. Data points with HD numbers in panels b and c were not used in calculations. If the same data points were also not used in panels a and d, calculated correlation coefficients were equal 0.56 and 0.53, respectively.