If you're not familiar with the YN-622 trigger you can get your update here Review Yongnuo YN-622. The new YN-622-TX is a welcome addition to this series of wireless TTL triggers. While the YN-622 units are transceivers, the YN-622-TX is a transmitter only. Just like the YN-E3-ST it is able to control your flashes attached to YN-622 units without the need of the camera flash menu. While this is not too fancy it offers some additional features.
To keep this short: it can fire speedlited attached to a YN-622 receiver. Nothing new, right? Don't get me wrong, this was a surprise some years ago but today this is welcome but not stunning. A USB-port might bring some improvements later on.
Imagine you want to setup the background light on group C. Instead of running to all your group A/B units you can simple press one key on the YN-622-TX and they are disabled. Very nice.
Using the on screen display of the YN-622-TX you can set up different flash modes for group A/B/C individually. Using group A/B in TTL mode and group C in manual mode? No problem. Just press some keys and you're done.
Yeah... it's still there ;-)
The on screen display clearly shows the zoom setting for each channel and allows to change them in the way you need them. From my perspective this nicely done. It is enough to press a key to jump from group to group and adjust those settings. Maybe they'll support 200mm instead of 105mm in the future.
The package just came in some days ago and there was not too much time to check everything out. But it seems that this device works somehow ;-) For everybody who uses the YN-622 this is some kind of must have. Checking the settings of remote speedlites and adjusting them can't be much easier. The integrated GR-support is a very welcome feature. If you use a newer Canon camera you can even use the camera flash menu to setup things. But if you're already on the Canon RT train all this stuff is not very impressive and kind of step back. Hope they release the YN-600-RT soon.
If you want to check the manual you can find it here YN-622-TX Manual.