Can anyone from Canon offer an opinion or reason as to why the 1Dx does not have the capability to communicate wirelessly with the 430EXII? It seems strange that my 2 year old 7D can do it but yet the 1Dx cannot. Was this to force customers with this flash towards the 600EX-RT? I'm guessing that this has been a deliberate action by Canon, i.e. to make them incompatible for wireless communication. When I tried to hook them up I was baffled that the settings would not register the flash, turn on the 7D and there it is.
Strange decision Canon but an explanation would be appreciated.
Ah, gotcha. I was a bit baffled, because for some of Nikon's pro bodies, I think they still have a pop-up flash, and I wasn't quite sure if that was the same for the 1D series since I haven't worked with them firsthand.
If I remember correctly, the 7D and T3i's pop-up flashes can do wireless control, so I'd assume the T4i does also. Not sure about the 60D, though. For the "pros", I think Canon is pushing for their new ST-E3-RT transmitter and 600EX-RT's -- great for someone with the $$ starting out or to sell their existing gear to upgrade, but I don't think Pocket Wizard / RadioPopper, etc are going out of business anytime soon.
Currently the T3i (600D), T4i (650D), EOS 60D and EOS 7D all can use their pop-up flash to contol other speedlites using the pulsed light communication.
There are some differences though.
T3i / T4i / 60D - control at most 2 groups of flash, Speedlite groups A and B
7D - control 3 groups of flashes Speedlite groups A, B & C.
None of the built-in flashes can force the slaves to high speed sync mode.
To be honest I think Canon missed a trick by not building an ST-E3-RT type transmitter inside the EOS-1D X, though maybe getting radio signals through the metal body was the issue.