In this Letter, we develop a novel technique, to the best of our knowledge, to increase the link span ($ {L_s} $Ls) of a rolling shutter (RS)-based optical camera communications (OCC) system by reducing the spatial bandwidth of the camera in the out-of-focus regions. We demonstrate a 400 m line-of-sight RS-based OCC link, which is to date the longest $ {L_s} $Ls reported in these systems, and develop a detection method to extract the information out of the video frames, successfully. The proposed system relaxes the condition of a large surface area for the transmitter light source. Consequently, we show that at 400 m $ {L_s} $Ls and exposure times of 100-80 µs, a data rate of 450 bps is achieved successfully.