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EOS 80D: Godox off camera flash not working


I have a Canon 80D and a Godox TT350C flash unit, which is supposed to operate as a wireless off camera flash, however I can't get it to fire. Gone through both manuals, can't see what I'm doing wrong.

Any help would be appreciated




I'll ping one of our flash experts, but my initial recommendation would be to use a Canon flash with your Canon camera.  

Bay Area - CA

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Your speedlite only supports the newer RF communication protocol. Your EOS 80D only supports the older line of sight optical system via the built in flash. Theses 2 systems are incompatible with each other. You will an RF transmitter in the hot shoe to trigger the off camera flash. The old optical system fires a modulated pre-flash before the shutter opens to fire off the off camera flashes. 


Current Gear: EOS 5D Mark IV, EF F/2.8 Trinity, EF 50mm F/1.8 STM, EF 85mm F/1.8 USM, 470EX-AI & 600EX II-RT

Retired Gear: EOS 40D


To fully utilize your Godox TT350 as an ETTL off camera flash, you will need to buy a Godox TTL radio transmitter for your Canon 80D.


Don’t buy a Canon radio transmitter as Godox uses a different wireless protocol, and is not compatible with the Canon ST-E3-RT transmitter. 

In addition to the radio wireless capability, the TT350 also a basic S1/S2 type “dumb” optical slave flash which should work with the built-in flash on your 80D(or any flash). This will only work with the Godox flash in Manual mode. 

There is nothing in the 80D manual about using “dumb” optical slave flash, and very little in the Godox TT350 manual. Put the TT350 in manual mode and then use the “slave” button to select either S1 or S2 slave mode. 

S1 will fire the slave flash anytime it sees a bright flash of light. Use this mode if you are using the 80D built-in flash in Manual mode. 

S2 will fire the slave flash when it sees a secondary flash after the ETTL pre flash. Use this mode if you are using the 80D built-in flash in ETTL mode. 



Mike Sowsun
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