Canon ir vs pocketwizard mini/flex

[inkista]

If third-party, often-flighty Pocket Wizards can send shutter speed information, then Canon can probably handle it too.

Uh, not... really. The PWs and YN-622c/Photix Odin/Pixel Kings are basically just relaying all five signals on the hotshoe. We know the hotshoe can do 2nd-curtain. The wireless protocol is not the hotshoe. When you invoke Canon's wireless protocol with any of these triggering systems, then you lose 2nd-curtain. With the YN-622c triggers, if wireless is enabled in the camera menu, you no longer have access to 2nd curtain.

... Really, I'm not sure why 2CS isn't the default setting for on-camera and slave flashes. ...

Probably because you're using relatively normal shutter speeds and never shoot eTTL . With eTTL, once your shutter speeds get low enough, the delay between the preflash and the actual flash with 2nd-curtain might be enough that your subject is caught full-blink (or in motion) on the actual flash burst. With 1st-curtain, you have the absolute shortest delay between preflash and main flash.

[RustBeltRaw]

Uh, not... really. The PWs and YN-622c/Photix Odin/Pixel Kings are basically just relaying all five signals on the hotshoe. We know the hotshoe can do 2nd-curtain. The wireless protocol is not the hotshoe.

Sorry, that statement was rather imprecise. The fact that shutter speed info is on the shoe is clear since the PWs can send it, I'm just surprised that Canon doesn't have a wireless system (protocol) that does so.

Probably because you're using relatively normal shutter speeds and never shoot eTTL . With eTTL, once your shutter speeds get low enough, the delay between the preflash and the actual flash with 2nd-curtain might be enough that your subject is caught full-blink (or in motion) on the actual flash burst. With 1st-curtain, you have the absolute shortest delay between preflash and main flash.

Not sure I follow. Are you saying that 2CS isn't the default setting because the pre-flash can sometimes illuminate the subject at the start of exposure? I've certainly had that problem, but even so, I don't know of any cases where you'd want to freeze motion at the start of exposure.

[inkista]

... Not sure I follow. Are you saying that 2CS isn't the default setting because the pre-flash can sometimes illuminate the subject at the start of exposure? I've certainly had that problem, but even so, I don't know of any cases where you'd want to freeze motion at the start of exposure.

No, what I'm saying is that if you are a snapshot shooter who wanders down to, say, a 1/15 or 1/8 second shutter speed with 2nd-curtain and eTTL, then there's enough separation between pre-flash and main flash, that the subject may mistake the first for the second, and you get a portrait with the person's eyes closed.

Canon likes to idiot-proof stuff.

[Colin Southern]

Uh, not... really. The PWs and YN-622c/Photix Odin/Pixel Kings are basically just relaying all five signals on the hotshoe.

Kinda, the PW does it a little differently though in that it "translates" that into it's own protocol along the way, with a few "secret sauce" ingredients thrown in for good luck (eg the ability to quadruple the pre-flash power (and presumably compensate the corresponding flash power instruction), and correct a 2nd curtain synch mis-timing that they feel Canon has, whereas the likes of the radio popper just "re-package" the signals faithfully.

[RustBeltRaw]

No, what I'm saying is that if you are a snapshot shooter who wanders down to, say, a 1/15 or 1/8 second shutter speed with 2nd-curtain and eTTL, then there's enough separation between pre-flash and main flash, that the subject may mistake the first for the second, and you get a portrait with the person's eyes closed.

Canon likes to idiot-proof stuff.

Apparently so. I guess avoiding blink by taking multiple shots when doing flash portraits isn't as basic a technique as I thought. But I have had that problem (usually on the first shot in a rapid series) with slow shutters and 2CS, so there's clearly some merit to Canon's decision.