What's the difference between RadioPoppers and Pocket Wizards? Several of you have emailed me about this, as you try to figure out how to spend your money.
I'm not going to be able to speak to technical issues, like what radio frequencies are used or what sorts of situations will cause interference or anything like that. But I can tell you some things from a users perspective.
First off, RadioPoppers are ONLY going to work on i-ttl or e-ttl -enabled flash systems. So you have to have the Nikon SB-800 (or the SB-900's when they come out) or the SB-600 flashes, or whatever the Canon models are that work with their system. They take advantage of that annoying little "pre-flash" that occurs just before the exposure to let the various strobes communicate with the camera, by extending the useful range of that communication. But if you've got a Vivitar 283, or an SB-24 or any other flash, you're out of luck.
On the other hand, if you've got any flash with a PC sync input, you can use it on manual with Pocket Wizards and you'll be happy as a clam.
Pocket Wizards, in their current generation anyway, are basically just transmitters and receivers. Granted, you can pick different frequencies in case there are other photographers around competing with you, and they have some other bells and whistles too. They're amazingly reliable, and I've almost never had them fail even when I'm hundreds of feet away and firing strobes inside buildings and behind walls and other cool stuff. They sip battery juice ever so lightly, and I can put a pair of AA's in and then not worry about having to replace them for months, tens of thousands of frames later. I use my Wizards to trigger any and all of my flashes, including my beloved Alien Bees.
So far my RadioPoppers seem to be just about as versatile. They work from a long ways away and seem to be mighty reliable. I have noticed that they use up batteries a little faster, to the point where I am putting a set of freshly-charged NiMH's in them before each Saturday's wedding.
But the really amazing thing about Radiopoppers that sets them apart is this:
YOU CAN ADJUST YOUR FLASH'S POWER OUTPUT FROM THE CAMERA.
Let that soak in for a second.
Say you're 60, or maybe 75 feet away from your subjects, and have a flash set up a few feet from them, triggered by i-ttl and RadioPoppers. The sun's going down, so the ambient is changing each minute. You shoot a frame and decide after chimping that your flash is too hot.
Instead of having to stop shooting for a couple minutes to run over and adjust the power setting on your strobe, you can just dial it down right there from your "master" flash unit (or your camera if you're using the pop-up flash.) If you took the power down too far, you can just run it back up a bit without having to take the trouble to jog up to the flash and mess with it.
Personally, I think that's amazing.
And I'd like to point out that I really hate to fumble with stuff in front of my clients. Whenever I have to stop shooting and go make an adjustment and explain it ("that darned flash just isn't giving me the right amount of light!") I end up feeling like I must look like an idiot. There are plenty of other ways I can look like that, so I don't need my equipment lending a hand to the effect.
I can tell you that I will continue to bring along my Pocket Wizards to just about every shoot, and there are lots of situations where I set up a light and then don't have to mess with it while I'm shooting. But there are lots of situations where I can imagine using the RadioPoppers exclusively, and I've done that several times so far. They do work fairly well in ttl-mode, which I've explained in another post, but in most situations I'm using the flash on manual settings because that's more reliable.
Both systems are going to set you back three-to-four bills for a transmitter and receiver. And once you have one, you're going to want some more. Two days after trying out my first batch of RadioPoppers, I bought two more receivers. Now I can have multiple flashes firing at different settings and I can adjust them all without having to walk around from flash to flash, just by changing the settings right there while the camera is hanging around my neck.
But remember: RadioPoppers are designed to work with a small subset of all the types of flashes that are out there. For that job they seem to work really well, and they just might revolutionize how future flash systems are designed. Wizards are going to work with a lot more types of strobes, including big studio systems, but they give you less flexibility of the kind I've described here.
Either way you go, you expand the capabilities of what you can do in lighting, and it's worth the expense.