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ST-3, 600 EX-RT and Canon R5: ETTL and connection issues

ChristineMcN
Contributor

Hello, 
I haven't used by St-3 trigger and Canon 600 EX-FT flashes much with my R5.. but when I have, they have worked fine. 

All of sudden, they are behaving as following: 
- when i first connect them, the greens activate rapidly and the first image fires no problem BUT - I can't switch the flash unit out of ETTL mode (not manually on the flash, or with the ST-3) 

- if the camera/units idle for a couple of minutes, they disconnect and the flash switches to LED Red 
- I then can't reconnect them easily - and when I do, they behave the same way - one or two shots, and then revert to being disconnected. 
 
Thank you for guidance on how to fix this problem. 

 

 

6 REPLIES 6

onlysublime
Enthusiast

extend the time your R5 goes to sleep.  When the camera goes to sleep, you will lose connection and it won't come back until you powercycle everything.  that solved all the disconnects for me.  by the default, the R5 goes to sleep after 3 minutes?  I forgot.  I set it to 30 minutes.

daniel598lopez
Apprentice

@ChristineMcN wrote:

Hello, 
I haven't used by St-3 trigger and Canon 600 EX-FT flashes much with my R5.. but when I have, they have worked fine. 

All of sudden, they are behaving as following: JoinPD
- when i first connect them, the greens activate rapidly and the first image fires no problem BUT - I can't switch the flash unit out of ETTL mode (not manually on the flash, or with the ST-3) 

- if the camera/units idle for a couple of minutes, they disconnect and the flash switches to LED Red 
- I then can't reconnect them easily - and when I do, they behave the same way - one or two shots, and then revert to being disconnected. 
 
Thank you for guidance on how to fix this problem. 

 

 


Hello,
To resolve your Canon 600EX-RT and ST-E3-RT issues with your R5 camera, you can try the following steps:

  1. Check Connections: Ensure all units are securely connected.

  2. Reset Settings: Reset your flash and transmitter settings to default.

  3. Firmware Updates: Ensure all devices have the latest firmware.

  4. Battery Health: Use fully charged and healthy batteries.

  5. Compatibility: Ensure compatibility settings between camera, flash, and transmitter.

These steps often resolve common connectivity and mode issues. Anything else you'd like to know?

Best Regards,
Daniel Lopez

p4pictures
Elite
Elite

Two questions, do you use the auto radio channel or channel 1, and have you changed the ID from the default 0000?

I've used the Canon RT flash system since its introduction back in 2012, and I've not seen the disconnects that others have seen and reported. I always change my devices so that the ID is never 0000 - all other devices come from the factory set to 0000 so I avoid the risk of clashing with another photographers kit by not using the default ID. Secondly you can use the scan feature to determine which radio channel is the optimum in the environment you are working. Though for my needs I rarely change channels and typically use channel 4 or 5. 

In the past I have done demonstrations of Canon Speedlites are photo trade shows, I worked out that setting the ID to 5555 is the one that takes the most button presses for any audience visitor who might try to see if they can randomly trigger my flashes from the crowd as a joke 😁 however I don't use 5555 either.


Brian
EOS specialist trainer, photographer and author
-- Note: my spell checker is set for EN-GB, not EN-US --

Thank you - this makes total sense as I was having this problem while taking a portrait, then waiting a few minutes for the next person, and camera would have gone to sleep. Great! 

ChristineMcN
Contributor

Thank you ! I think the issue was more linked to my camera 'going to sleep' - but this advice also makes good sense for general practice. 

Best of luck!  Let me know how it goes.  It drove me crazy why I was getting disconnects and it finally dawned on me the sleep aspect.

Holiday
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