Canon 600EX II-RT drops link- HELP!

[Phillyphoto]

Scenarios I have tried: 

Using Canon Transmitter ST-E3-RT as the master and (2) 600 EX II-RTs as slaves.

Using A 600EX as master and B 600EX as slave.

Using B 600EX as master and A 600EX as slave. 

I get the same result of the slave dropping link. The time varies. Sometimes it drops link in 4 mins, sometimes 10mins, sometimes 20 or more minutes. The only way to relink them is by turning everything off and back on.

All channels are the same. Yes, I have scanned for the best connection as well as every other channel and AUTO.

All IDs are the same. 

Not near a wifi-router or airport, I'm in a row home in Philadelphia. 

Using NiMh rechargeables and using freshly charged batteries for every test. Batteries are about 2 years old. 

I have spoken to 2 Canon service reps and neither of them has any idea what the problem is. I really don't have the money to spend on sending everything in for "repair". 

Any help is greatly appreciated, thanks!

[JLCKJC]

I was considering the same thing, so I did some research and eventually contacted Godox with my question about compatibility with the R5 and other recent Canon mirrorless cameras. Here is my question to them followed by their reply.

Question:

Your web site lists compatible Canon EOS cameras that work with the Xpro-C TTL Wireless Flash Trigger. This list does not include the R5 or other recent Canon mirrorless cameras. Are/will they be supported?

Godox Reply:

Thank you for your interest in our products. 

For Canon R5 camera, our products （includes XproC）are compatible with it, but not fully compatible.

That is, there is an incompatible issue when using the wireless TTL mode and the HSS function simultaneously.

Perhaps there are camera limitations or compatibility issues to resolve.

Apparently, it is not an easy technical question for us, but there is no doubt that we are devoted to improving Godox's user experience.

Our technicians are still working on this problem and trying to find a solution.

We apologize for any inconvenience caused. I appreciate your cooperation and understanding. 

Wishing you a good weekend!

I decided to continue my search for other alternatives.

[crlyhds]

Thank you

[crlyhds]

Any issues?

[Steppy]

I've always used manual control with my R5, Godox XProII-C and X2T-C controllers, AD400Pro flashes and X1R-C adapters for my 600EX-RT flashes. The comments about TTL+HSS issues intrigued me so I performed some tests.

According to reports on other forums, the flashes just give out a full power flash with these settings and can't be controlled. I tried all combinations of controller with flash types and TTL+ HSS performed identically to TTL alone. All combinations exposed "correctly"(see later).

Some reports implied the firmware for the X2T-C had been updated to support the R5 and the release notes showed the following:

V1.3
To add the support for R5 camera (R5 camera firmware should be upgraded to V1.50)
2023-07-05

My X2T-C has firmware V1.4 and the XProII-C (note version II) is new, so presumably never suffered from this issue.

There are reports of issues with the R6 and R7, presumably due to differences introduced with the new hotshoe but I don't have either of these cameras so I can't comment.

According to Canon the 600EX-RT and ST-E3-RT are compatible with both the R5 and R6 so I don't see what could have changed if Godox are emulating these devices.

Although my tests appeared to be successful, the flash exposure was controlled, I found the exposure to be around ½ stop too bright. This correlates with other reports. Compensating around -1/3 stop was sufficient. However, I found the changes in settings of +/- 1/3 stop changed the exposure on average by roughly double this amount. Sometimes more, sometimes less. I repeated the same tests with my Phottix Laso setup and the exposure steps reliably matched the controller settings. I didn't compare to the native Canon RF system because I didn't want to waste my time, but I'm sure it would have been accurate, for 5 minutes at least.

[JLCKJC]

Thanks for the detailed testing and report. It sure appears that in your case the Canon R5 performed well with Godox triggers & adaptors for the 600EX-RT flashes with TTL-HSS flash mode active. So now I'm puzzled by the comment I received in just the last few days from Godox support stating that there is "an incompatibility issue when using the wireless TTL mode and the HSS function simultaneously." I guess it's safe to say "your mileage may vary, so buyer beware."

[Steppy]

In your post you referred to the Xpro-C, whereas I use the XproII-C, the newer model. I'm not sure whether the Xpro-C has been updated for the R5.

[Steppy]

I just checked the latest firmware for the Xpro-C. Its v2.0 from 2020-12-19, so I'm guessing it's not compatible with the R5.

[JLCKJC]

I'll ask the same question about the XproII-C. If I receive a reply I will post back. Thanks again.

[JimOsdale]

No problems at all. 

[JimOsdale]

The Godox transmitter works just fine for me on my R5, no issues and it stays connected. I've seen some posts where images were off by 1/3 stop or so, but in this world of digital, who cares? EVERY image is run through Adobe Lightroom, Photoshop, or alternative image software for adjustment. I'd be willing to bet, there is not one professional photographer out there that provides an "untouched/unaltered" photo to the client or print shop for printing!