Equivalent stimulated Brillouin backscattering (SBS) saturation levels have been measured in the interaction with 0.527 and 0.351 microm laser beams demonstrating that the initial interaction wavelength is not influencing the final saturation levels. Experiments have been performed at the two wavelengths in similar interaction conditions obtained by preforming the plasma from a solid target with a creation beam converted at the same wavelength as the interaction beam. This produces an almost exponential density profile from vacuum to the critical density of the interaction beam in which large SBS gains are reached.