The FreeWave Captain Wireless TTL Receiver for Canon E-TTL or E-TTL II from Vello is part of a multi-purpose 2.4 GHz, 4-channel digital TTL radio system that gives wireless freedom from a PC cord plus the convenience of accurate exposures through wireless communication with your camera's E-TTL or E-TTL II flash technology.
Coupled with a separately purchased FreeWave Captain Wireless TTL Transmitter, the system not only enables remote triggering but also camera control with auto exposure in a radius up to 300'. Solo shooters can add depth to portraits and group shots by attaching a receiver to an E-TTL or E-TTL II flash mounted on a stand for hands-free shooting. Using 2 shoe mount flashes, an additional receiver and an assistant you'd have enough mobility to light groups, demos, shows, portraits and events on location, on-the-fly. And the benefits aren't limited to flash photography either. You can also use the receiver with the included camera cord and handhold an optional transmitter to wirelessly trigger your camera in single shot, continuous shot, bulb, and timer modes, with or without flash. This is of paramount importance in situations where a subject, such as wildlife, may be difficult to approach. Additionally, the wireless function of the device reduces the potential of camera shake when doing macro, close-up, and long exposure photography.
The Vello FreeWave Captain Wireless TTL Receiver's High Speed Sync and Second Curtain Sync functions create easy to control lighting effects and other creative options such as stop-action shooting and a wide degree of background or ambient light control.