Top: map in orthographic projection of the 150 GHz amplitudes at ℓ = 80, computed from the Planck 353 GHz data, extrapolated to 150 GHz, and normalized by the CMB expectation for tensor-to-scalar ratio r = 1. The colours represent the estimated contamination from dust in r_d units (see details in Sect. 5.3). The logarithm of the absolute value of r_d for a 400 deg² patch is presented in the pixel on which the patch is centred. As described in Sect. 3.3.2, the patches overlap and so their properties are not independent. The northern (southern) Galactic hemisphere is on the left (right). The thick black contour outlines the approximate BICEP2 deep-field region (see Sect. 6). Bottom: associated uncertainty, σ(r_d).