Cheapest flash that will work with in-camera trigger

so the question is basically in the title. I don't have a camera with a wireless trigger built in to it, but I'm probably going to grab a 70D sometime soon, and at the same time had been thinking of grabbing another speedlight of some sort that i could use as a second light source. I could see myself grabbing the light before the camera, and I'm wondering if the yongnuo flashes will work with the cameras trigger

right now i have those cheap ebay triggers, and a sync cord, and i'm hoping to not have to use them in the future as they both provide some limitations

i'm assuming it has to be an EX flash then?

I think the YN-510EX is the only one that has the capability of operating as an optical slave with the Canon system. It will work in full ETTL (HSS, FEC, FEB, Rear-curtain sync, FE lock, Modeling Light, Canon camera menu accessible) when off camera as a slave but is only full manual when mounted on camera or a YN622c

The YN-510EX is the cheapest,

But the YN-560EX is about $5 more and give 1/2 stop more light,

And then the YN-565EX is only $10 more and will work with ETTL radio triggers and on camera in TTL as well (which the 510EX and 560EX won't do) and adds an external battery socket.


So its generally really not worth limiting yourself to an optic wireless only flash for the sake of $15.


And if you're finding the ebay triggers and sync cord have limitations, your probably not going to be thrilled with working with the optic wireless system either.

You're generally much better off just grabbing a set of YN-622C (and compatible flash like the 565EX, 568EX or 500EX). Its really not worth trying to cut corners when these are relatively very inexpensive now anyway.
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