YN622c with430EXII... pass through

[Bugman]

T5i, yn622c triggers. the 430 EX II works great when mounted to a receiver trigger remotely. full TTL function. The problem is that When the yn622c is mounted on the camera hot shoe, with the flash on top of that, the flash just fires manually - there is no TTL pass through.

am I missing something, is there something I need to adjust, or are these just faulty switches that need to be replaced?

[RobertTheFat]

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@Bugman wrote:
T5i, yn622c triggers. the 430 EX II works great when mounted to a receiver trigger remotely. full TTL function. The problem is that When the yn622c is mounted on the camera hot shoe, with the flash on top of that, the flash just fires manually ther is no ttl pass through.

am I missing something, is there something I need to adjust, or are these just faulty switches that need to be replaced?

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Are you talking about TTL or ETTL? If you're not sure, that could be at least part of the problem. The two protocols are not the same. My impression (which may very well be wrong) is that Canon speedlights can be set to use TTL, but that recent Canon cameras must use either ETTL or manual mode.

[Bugman]

I sure don't know any of the science of TTL vs. ETTL.

But I can say that the Flash mounted ON the T5i hot shoe, works great in ETTL mode. The ETTL just doesn't work if there is a tranceiver placed on the hot shoe, between the camera and the flash.

The T5i is a type A camera using ETTL II.  The 430 EX II speedlight supports ETTL II -.  the YN 622C transceivers support both ETTL and ETTL II.  So they are all supposed to work perfectly together.

Summary:

1. Camera-hotshoe transmitter ----->across room --->  receiver trigger mounted-ETTL flash:    all works great.

2. Camera-hotshoe ETTL flash:   all works great.

3. Camera - hotshoe trigger - Flash mounted on top of trigger in ETTL mode for pass-through:    NO ETTL.

(flash fires ok as pure manual flash, but if I set flash to ETTL, get a totally black picture).   Meanwhile, the ETTL settings from the hotshoe tranceiver ARE transmitted across the room to my other transceiver, and the remote OFF-camera flash fires perfectly  with ETTL settings.

So the triggers actually work to receive and transmit ETTL 30 feet across the room, but each trigger alone will not pass the ETTL signals 1 inch from the bottom of the transceiver (camera hot shoe) to the top of the transceiver (the transceiver hot shoe, where the flash is mounted).

Question: either

1.  I actually bought two YN622C tranceivers both with the same defect?  or

2.  there is nothing wrong with the YN622C units - they are working as intended (but this doesn't make sense because they claim to be fully compatible with 430 EX II, and claim to have full ETTL pass-through).   OR

3. The YN622C units are not working for ETTL pass-through because of some camera, trigger, or flash setting I don't know about.

Thanks for any help you can offer. 

The T5i, 430 EX  II and YN622C are all very popular amateur products.  Hopefully there are lots of people who have used this combination successfully and can point me in the right direction.