Flash recommended by Ricoh.
TTL Flash Metering, On Camera flash compensation controlled as well.
As you see it dwarfs the camera for all this.
It weighs as much as 3 GRD's.
Or Sunpak PF20XD
Tiny, light, 3 auto levels, full range of manual power out put.
Covers 28mm field of view easily.
Has pull up diffuser giving excellent coverage with 21mm efl GW-1 installed on GRD.
Guess which one I use most