Conclusions: Low-power visible and infrared laser light was capable of modifying copolymers made from sulfur and either cyclopentadiene or dicyclopentadiene. The modifications were rapid, with exposure times on the millisecond to second timescales. Control of the power and wavelength enabled the installation of spikes, raised dots, pits and channels on the polymer surface. Inclusion of g-Fe2O3 nanoparticles in the polymer matrix facilitated the modification at lower laser powers, which was important for modifying the high Tg 50-poly(S-r-DCPD) polymer.