Ricoh GF-1 External Flash Description. The Ricoh GF-1 External Flash is designed for the GXR camera system including the GR Digital Camera. The GF-1 attaches to the camera body via the hot shoe. However it is independently powered using 4 AA batteries. Highlights of the GF-1 include TTL flash using pre-flash a built-in wide-angle diffuser & catch light panels. When the wide-angle diffuser panel is used coverage of 18mm is possible.