Canon R8 high speed synch - black frame every time

[Simon_2]

I am trying to use high speed synch, but I get a black frame every time, no matter what shutter speed is used. HSS is selected in the flash function settings on the camera and the HSS icon is showing on the trigger and strobe. The camera is in manual mode, with autofocus on. What am I doing wrong?

Devices & firmware used:

Camera body: version 1.4.0

RF 50mm 1.8mm STM: version 1.0.0

Godox XPro II trigger: version 1.4

AD100Pro: version 1.2

[deebatman316]

Are you using the Fully electronic shutter? If so the flash won’t fire. It will fire with Electronic First Curtain Shutter. This camera doesn’t have a Full Mechanical shutter like other cameras such as the EOS R6 Mark III. Have you tried a slower shutter speed than X-Sync. Such as 1/60th sec as a test to see if you still get a black frame. Is this the Canon version which supports E-TTL II. The name would say Godox XPro II-C. If it doesn’t that version is just the manual flash version. It doesn’t interface with the camera for E-TTL II support at all. Is it slid in properly if not it won’t fire at the correct time. Or it could just be simply be INCOMPATIBLE with the EOS R8.

[Simon_2]

I am using the Electronic First Curtain Shutter. At 1/200 the flash fires and the camera takes a picture. At anything above 1/200, I get a black frame every time. The ISO keeps switching to Auto as well.

I have used this Godox trigger with the R8 and the flash set to its normal range and it works then.

[deebatman316]

Godox flashes and triggers are known to have INCOMPATIBILITIES when using HSS with certain cameras. If regular flash works correctly then it is known that HSS is NOT COMPATIBLE. I would use a Canon speedlite to see if it works correctly. If it does then the trigger is the problem. Also try the Godox flash on camera too. This is a known problem with cameras that lack full mechanical shutters.

[Simon_2]

I should add that I have just tried the R8 with a Godox V1 speedlite attached and HSS worked. So the problem may not be with the camera but with the signal to the AD100Pro, or with the strobe itself perhaps?

[deebatman316]

The trigger may NOT be COMPATIBLE with your camera. Is the trigger the Canon version ie the name is Godox XPro II-C? If not then HSS won’t work. If it is the Canon version then it may not be compatible. Just because a product says “Compatible” with Canon. Doesn’t mean it really especially when it was released before the camera. I would also check with Godox to see if there’s a firmware update available to make it work. If not it’s just INCOMPATIBLE. 

[Simon_2]

Yes, the trigger is the Godox XPro II-C. I have used it successfully with this camera and with my 90D. It is only now when HSS is activated that there have been problems.

[deebatman316 · Accepted solution]

I believe that particular Godox trigger is NOT COMPATIBLE with the EOS R8 when set to HSS. This is a very common issue with Godox’s gear. Especially on cameras that lack a full mechanical shutter such as the EOS R8. Other Godox flashes have this problem too.

[Simon_2]

Thank you. I will look into it.