@Reg_gie Log into the camera and set up the main and sub stream to what resolution frame rate etc your wanting (suggest also h264 encoding).
Some cameras indicate in the settings what it should be, but something like the following should work;
rtsp://user:pass@ipaddress:[RTSP PORT]/media/video[STREAM TYPE]
or
rtsp://user:pass@ipaddress:[RTSP PORT]/Streaming/Channels/[STREAM TYPE]
Port is normally 554, but again this can be configured on the camera, Stream type will either be 0 for the main stream and 1 for the substream.