Looking for a stand alone AF Assist Light to use by itself, or with other radio triggers that don’t have one? Well YongNuo already have one available of sorts in the YN-622 –
The inexpensive YN-622 are now fairly legendary, highly capable, TTL wireless radio triggers. But for less than $50 per unit, you can afford to forget about what they were designed for, and use one just as a stand alone AF assist light on the camera. Or with other radio transmitters mounted on top.
The YN-622 may not be the absolute ideal stand alone AF light, but after years of harassing manufacturers to make a purpose built unit, its becoming pretty obvious that’s not going to happen now. (Not by the current radio trigger manufacturers anyway, as its simply not in their interest to provide solutions for the opposition). So for now the YN-622 are really the best current inexpensive solution for Canon and Nikon owners.
The YN-622 AF light itself is mainly designed for just center focus point (though you may squeeze a few more in there), but the lazer style contrast line pattern is very sharp and bright compared to the Canon/Nikon offerings. So for a center focus point use I find its actually a very capable AF light. (Much better than regular torches without contrast projection, not to mention much less clumsy).
The main catch with the 622 though is that the TTL pass though hotshoe on top is not strictly a direct pass through. This means that any TTL information is running through the YN-622’s processor, not directly passed straight through from camera to the device mounted on top. So basically any TTL capable device mounted on top still needs to cooperate and communicate with the YN-622, and not just the camera.
So basic manual triggers mounted on top are generally fine, but any units with TTL capability may have limitations. Though there are some good results with the Pixel King Pro and Phottix Odin as noted bellow.
Most basic manual triggers appear to work fine on top of the YN-622 pass through hotshoe. I tested a number of transmitters on top of the YN-622C previously and didn’t see any issues there. Considering very few of the manual triggers have any AF assist light built in, this can be seriously handy.
(One exception I know of that doesn’t work is the Godox cells II, but that is a specialized manual trigger with HSS capability, and known not to work on anything but directly mounted on the camera hotshoe).
YN-622C settings - I don’t think there are any settings to worry about here with manual triggers, just make sure the YN-622 and well seated in the camera hotshoe, and the likewise the transmitter mounted on top of the YN-622 hotshoe. Also the YN-622 must be switched on for the transmitter on top to work. That can be easy to miss at the start, but you soon get used to checking that first if the flash is not firing.
I have only tested these with the Canon version YN-622C, if anyone runs across any compatibility issues with the Nikon version YN-622N please let us know, thanks.
Pixel King Pro
The trick with the Pixel King Pro is simply to mount the YN-622C on top of the King Pro’s pass through hotshoe (instead of the other way around this time).
There may be some limited functionality with the King Pro mounted on top of the YN-622C instead, but with the YN-622C on top I get full functionality with the King Pro. And its much better to have the YN-622C on top anyway, because if that is switched off, or has any issues, its not blocking signal between the camera and King Pro.
So with the Canon version at least I get full functionality with the King Pro, ETTL, Remote Manual, HSS, and Second Curtain Sync.
The Nikon version King Pro is quite different though, as that takes control of the slave flashes, always set to TTL. So there is some possibility the Nikon version may have more limited function. If anyone can provide feedback on this it would be very appreciated thanks.
YN-622c settings - Again I don’t think there are any settings to worry about on the YN-622C while its mounted on top of the King Pro. You can switch the YN-622C on and off as needed for the AF light, and the King Pro functions as normal.
Because the AF light is mounted a little higher, within about a meter of the subject it may be a bit too high for the cameras center focus point. I found I could just loosen the YN-622C foot locking ring off just a little bit and it would tilt down fairly easily. A light rubber band wrapped around both triggers would likely do the trick to pull the light down a little if you were working that close often. Otherwise the YN-622C AF light generally works great on top of the King Pro.
With the Phottix Odin I get full function with Remote Manual, HSS, and Second Curtain Sync, just No TTL function.
Again I have only tested with the Canon version, but the Nikon version Odin works in a similar manner, so that is at least promising for Nikon. Although there is no TTL function with this set up, I’m still thrilled that Remote Manual, HSS, and SCS, are working great on top of the YN-622C.
I have tried the Odin’s like this before, but with very limited success. And I’m not 100% sure that its not also due to later firmware, or that I’m using the later V1.5 model Odin now, but I’m pretty sure the main issue was that I simply did not have the Odin seated all the way in the YN-622C hotshoe. Something was catching, and I never quite pushed the Odin all the way on properly. They are working very consistently together like this now though.
YN-622c settings - If the camera used has a flash control menu, you have to be mindful of the YN-622C setting set through the camera menu as well. If you want to use HSS or Second Curtain Sync, that has to be set on the YN-622C as well (through the camera menu), not just on the Odin transmitter. If they don’t match the Odin transmitter will keep bouncing back to whatever the camera/YN622C are set to.
The is not really an issue in practice, as long as you are aware of it. I just leave the camera/YN-622C set to HSS, and that way it will allow high shutter speeds (with HSS), but as soon as you go bellow the cameras X-sync speed it automatically turns HSS off on the flash (and back on again as needed). Setting Second Curtain Sync must be done in the camera menu, and “wireless mode” must be disabled in the flash control menu (as that is what the YN-622C requires for SCS operation). The Odin function as normal then with Second Curtain Sync.
Otherwise these work great together in Remote Manual (the Canon version at least). Phottix have recently released the Mitros + flash with Odin transmitter built in, so that will be the main AF assist light option (which will work in TTL as well) but the YN-622C combination is still a great option to have for the Odin transmitter if remote manual is mainly all you’re after.
From most reports the Canon ST-E3-RT doesn’t work on top of the YN-622C, but YongNuo have released their own YN-E3-RT transmitter, which has a built in AF-assist light, and is directly compatible with the Canon RT system. So that is a direct substitute for Canon’s ST-E3-RT, and likely at a lower price. So the YN-E3-RT would be much more preferable to stacking transmitters like this when avoidable.
I haven’t tested the PocketWizard TT1 or TT5 with YN-622C on top, so would be interested to hear any results. At best this would be very limited though, as without an AC3 zone controller (or master flash) mounted on top of the TT1 or TT5 on camera, there is one TTL group available only. The chance of any function after stacking an AC3 on top of the YN-622, on top of a TT1/TT5, I would imagine would be pretty slim.
YN-622 Price and Availability -
YN-622 are originally sold in pairs from around $85, though some sellers do offer single units around $45 – $50.
Purchasing from a local seller on Amazon, or Amazon Fulfilled, is often the proffered method, as you receive the triggers fast, and Amazon provide an excellent 30 day no hassle fast exchange if there are any issues. Purchasing from China may be a little cheaper sometimes, but postage times can be long, and if there is an issue return shipping from China can also be costly and time consuming.