The RadioPopper PX Receiver to take advantage of eTTL/iTTL, manual and High Speed Sync, all while avoiding the drawbacks of line of sight, short range and sunlight interference, you'll need a PX Receiver. For every off-camera flash you'll use, you will need a PX Receiver. Although the PX receivers and transmitters are compatible with Canon & Nissin, each receiver comes with a mounting bracket that is specific to either Canon or Nissin Flashes.
Reviewed by 3 customers
Best off camera flash solution for Canon 580EX, 580EXII, 430EX. Extends flash range and allows use of all modifiers. The bad is that these eat batteries, and start to fail when battery power gets down to 60% or so. Taking batts out after every use extends life somewhat. Not the easiest to store and transport.
Adorama asked me to review, so here goes... I decided to save a few $ and purchase a used unit from Adorama. One of my Popper receivers had failed me - not sure why yet, but it just stopped working. Anyway, the used unit arrived with dead batteries and with a defective Canon bracket. The receiver itself worked when I put good batteries in it, but I seriously expected to get "used" equipment, and not "defective" equipment. Since they gave me a full refund (including shipping), I will buy a brand new unit from them this time.
When these work, they're great. When they don't, it can make you look like an idiot in front of a client and leave you looking for another solution. These little guys have a very specific order in which they must be turned on relative to your flashes and camera in order to work properly. They always seem to work when I'm just playing around with them (after several minutes of turning things off and on and various orders), but when I'm on a job, I can never seem to get them to work. That, of course, is embarrassing when you're trying to do a portrait shoot, or wasting a business person's time while trying to conduct a corporate headshot session. Bottom line, I don't think I would buy these again. They are in my gear bag when I go to a shoot, but I never count on them working and always have to have a backup plan.