It's important to note that, when switching from \{(+,-,-,-)\,,l^a n_a=1\,,m^a \bar{m}_a=-1\} to \{(-,+,+,+)\,,l^a n_a=-1\,,m^a \bar{m}_a=1\}, definitions of the spin coefficients, Weyl-NP scalars \Psi_{i} and Ricci-NP scalars \Phi_{ij} need to change their signs; this way, the Einstein-Maxwell equations can be left unchanged.
so the following two pairs of cross-normalization are adopted .