Easy to Use, Powerful TTL Macro Ring Flash The Nissin MF18 Macro Ring Flash also has a built-in modeling light, can operate in optical wireless TTL master or slave mode, and has high speed sync compatibility. The Nissin MF18 is fully compatible with Sony E mount TTL systems (order the Sony E mount compatible Nissin MF18 version). Just plug it in to your camera and shoot. The MF18 has a GN of 16 meters/52 feet. Precise Light Control Macro Ring Flash The MF18 Macro Ring Flash allows precise fine tuning of light output from 1/128 to 1/1024 in 1/6 EV steps. While in Manual mode, the power ratio can be adjusted from full power to 1/64 in 1/3 EV steps.