I assume you have the R200s on the ring around the lens? Yes, the SC28 will work with the Su800. Also with the SB900. You can mount the SU800 or the 900 on a bracket attached to your camera, or on a nearby light stand. You'll be limited by the length of the cord of course. I am toying with a setup using the foot that comes with the SB900. I'll take a photo of the setup I made.