Processed prominence signals in the Hα line, the Ca II line, and the Ca I and Ti II line pair of the G-band, normalized to the local disk-center intensity. For the first row, a sum (gray box) is taken over the non-Gaussian emission profile to obtain the integrated line intensity of the prominence. A Gaussian was fit to the emission of the other two prominences. The best-fit parameters of these Gaussians are given in Table 1.