NGC 891. The yellow polarization vectors are in the H band, the blue polarization vecotrs are from radio sychrotron measurements by Sukumar and Allen (1991, ApJ, 382, 100). If both methods are measuring the same magnetic field geometry, they will be perpendicular to one another. Note that the magnetic field in the disk clearly departs from a simple planar field in the North and is at an angle of about 15 degrees to the disk of the galaxy.