Angular resolved normal emission photoelectron spectra of Cu(110) using linearly polarized light (ℏω = 21.22 eV) are presented. Within the frame of the three-step-model of photoemission corresponding spectra have been calculated and good agreement with experiment is achieved. Spin-orbit coupling is important and gives rise to a relaxation of single-group dipole selection rules even for low Z materials. Photoelectron spectra are critically dependent on external experimental parameters. All features in the experimental spectra may be interpreted by direct transitions.