The RadioPopper PX kit is an advanced radio transmitter and receiver kit for Canon that allows E-TTL triggering with compatible Speedlites. It basically piggybacks on the Canon wireless flash system giving improved performance. It offers a useable range of 1500ft (various conditions will lessen this). You’ll have freedom from line-of-sight restrictions, as well as more reliability. It has 16 user-selectable channels to ensure interference-free shoots.
Since it uses the Canon wireless flash system, you’ll need either an ST-E2 or Canon Master Speedlite on-camera to attach the PX transmitter to via velcro (included). The receiver then attaches to your E-TTL compatible Speedlite via included bracket. With the TTL information being transmitted, quick flash adjustments can be done through the Flash Exposure Compensation dial on your camera. It offers full compatibility with the High-Speed Sync mode, so sync speeds of up to 1/8000 second are possible (at the expensive of light output).
The PX transmitter must be used with one of the following Master units on-camera:
- Canon ST-E2 Speedlite Transmitter
- Canon Speedlite 580EX II
- Canon Speedlite 580EX
- Canon Speedlite 550EX
The PX receiver unit only works with the following Canon Speedlite flashes off-camera: