Ice absorption spectra at the three points marked in Figure 1 for CrA 151 (top row) and L1544 (bottom row). Brown denotes the spectrum from the cloud center, orange-red denotes that from an intermediate radius, and yellow is the spectrum from a point in the outskirts. The foreground flux I_fg is set to various fractions of the total off-core flux ﹩{I}_{{\rm{off}}-{\rm{core}}}﹩, and subtracted from the observed flux in the cores to compute the new spectra and optical depths. We see that for CrA 151 only very high values of I_fg can reverse the trend of τ_ice being lower at the center than at surrounding radii, and for L1544 no assumed I_fg can do that. The highest allowed value for the assumed I_fg is such that the foreground never exceeds the total observed flux at any position or wavelength.