The RadioPopper PX-T Transmitter (CE/Euro) maintains the ETTL/iTTL functions of your camera and flash while adding radio triggering that can fire your flash at distances of up to 1,750' depending on the prevailing conditions.
The transmitter, which comes loaded with both Canon and Nikon software, mounts to your master flash or commander and allows slave flash units equipped with an optional PX Receiver to receive TTL or iTTL signals by radio without the limitation of having to be in line of sight with each other. Put simply, the RadioPopper enhances your ETTL/iTTL system by allowing it to act like a radio slave setup.
The 16-channel PX-T Transmitter has an auto-search feature that seeks out the cleanest channel for use at your specific location. Several flash units can added to up to 3 groups that can be controlled and fired simultaneously or group by group. There are no wires or shoe mounts on the unit, instead the transmitter is touch-fastened to the top of your master flash. Alternatively, with Nikon cameras with pop-up commander flashes, you can mount the transmitter to a special pop-up adapter that allows unimpeded use of the integrated flash.
While DSLRs can use up to 1/250 second sync speed, the PX system also supports high-speed sync speeds up to 1/8000 sec. The PX Transmitter gets approximately 25 hours of power-on time from the two included AAA batteries. It requires use of an optional PX Receiver for normal operation.