Here, we evaluated the therapeutic potential of three channelrhodopsin variants: ChRmine, from the algae Rhodomonas lens, ChRmine-T119A, a faster-closing ChRmine variant, and ChroME2s, a second-generation Chronos-based opsin.We expressed these opsins in retinal ganglion cells of rd1 mice, a model of severe retinal degeneration. Here, PDE6B is linked to retinal degeneration.