I've written before about the very excellent Cactus V5 radio transmitter / receivers for your hotshoe flash. Great range, simple to use, and pretty much foolproof, so long as you understood power and exposure control were all manual. Then a seminar attendee was telling me of his challenges with off camera flash and how things would be solved by his new Cactus V6 set because the salesperson told him that they had TTL. Really? For about $160 a pair? I had to check this out.Let's get this cleared up right away. There is NO TTL in the Cactus V6 units. What there is, is some tech that profiles TTL flashes so you can control their output power through MANUAL settings from the transmitter. That is actually quite useful for lighting dorks as as myself, but regular users want wireless flash that works simply and painlessly, and without the line of sight limitations of infrared triggering that is built into most camera / flash systems today. Folks who want this need to move along, because the Cactus V6 systems don't do that.
What they do, is build on the V4 and V5 units to include four zones, with each zone having individual power control from full down to 1/128 power with compatible flash units. The flash unit list is decent and includes the usual Canon, Nikon, Pentax, Metz, Nissin, Olympus, and Panasonic suspects, along with Cactus brand flash units. The devices can also "learn" many unprofiled flash systems and operate them as well.
The confusion comes from the hotshoes and the feet of the units. They have multiple pins, just as you would find on a TTL flash. In fact the single unit has enough pins that they interface directly with Canon, Nikon and Pentax without having to choose a specific model.
At first glance in fact you would think you could control the flash from the camera menu itself, especially since you are supposed to set the unit configured for Transmit to the TTL setting. But when you try to access the external flash control menu, it tells you that there is no external flash installed. Much frustration ensues.
You would also expect that with all those pins, the camera would know that there was some kind of flash signalling device telling the camera about itself and that would give flash ready indicators and maybe even set the proper sync speed. Yeah you'd expect that, but over 70% of the time, the camera had no idea that the Cactus V6 was in the shoe, in TTL mode, powered up and ready to go. In fact after futzing around for an hour to try to determine what magic sequence was required for the camera to know that there was a flash trigger present, I just gave up.
When you do get the camera to see the trigger, and understand that you are setting the power output manually across up to four flash zones, the units become reasonably usable. They have a legible LCD panel, a decent menu system and easy to use zone controls. I was working in my studio and the zone LEDS were so bright that they looked like red lights. When I went to a much brighter room, I discovered that the red lights were actually letters, so that is even more useful.
I was very hopeful that the V6 would duplicate the incredible range of the V5 units. Sadly they resemble the performance of the old V4 units, where while you don't need line of sight, a couple of drywall partitions were enough to stop the radio signal from getting through. When I put the receiver with flash on it inside a Westcott Apollo Softbox, I had 30% trigger failure, possibly the metallic silvery liner impedes the radio signal. I've never had that happen with the V5 units, or Canon's radio, or the Profoto radio, or even the ridiculously expensive and requiring of a blood sacrifice cursed Pocket Wizard TT1/FlexTT5 units.
Each unit runs on 2 AA batteries (not included) and comes with a little stand. The unit can sit in a hotshoe or be mounted to a standard ¼-20 fitting on a light stand or tripod. There is a very easy to use lever lock to hold the unit in place on the hotshoe, and I credit Cactus. It's not beautiful but it is so much simpler and more effective than those silly knurled ring systems. Units are sold individually (about $80) each and come with a quick "lighting options" guide and a tiny manual. If your eyes are becoming more demanding, you will need magnifiers for the tiny print.
With an accessory cable, you can also use the Cactus V6 units as remote radio triggers for your camera. So if you happen to need to trigger a remote camera, this could be a useful advantage for you. My friend Bryan shoots pro wrestling, and it's an advantage to fly a camera above the ring and to be able to fire it from ringside on demand. You can do this with other trigger systems, including the Cactus V5s just be sure to order the right cable for your camera.
The units have a USB port for firmware updates, but for most every photographer I know this is pointless since it is a Windows only updater. I do understand that Windows has dominate marketshare overall, but more creatives I know use Macs instead of Windows. So for me at least, this makes the update functionality completely useless.
While the multiple zones are very handy, and the ability to control output power from the camera across four zones, and potentially multiple TTL flash vendors sounds good, I'm not convinced. I don't believe that the V6 system solves the flash control problem as well as the more expensive Pocket Wizard system and if you want real flash control from the camera, you are better off with Phottix Odin, Hahnel TUFF TTL or even Yong Nuo radio TTL triggers. Price point is one thing, usability is another. Not recommended at this time.