Maps of the polarization angle in degrees, measured relative to north, with B_HIGH filter. Left: NGC-3351 with the approximate location of SN 2012aw marked with a black cross. Right: NGC-4424 with the approximate location of SN 2012cg marked with a black cross. The patterns displayed are compatible with polarization due to the scattering of light of a dominating central source inside a dusty medium (see Appendix A). Milky Way stars are indicated with white circles. A flux image of the galaxies, using the same filter, is presented at the top left corner of each map.