Help needed with HSS set up on EOS R5

[David23]

Need help setting up my Canon Speedlite 430EXIII-RT with my R5 for HSS. Is this function possible?

[deebatman316]

If the camera is set to Full Auto it’s not possible. HSS can be set directly on the speedlite’s LCD Screen. Or it can be set via the Speedlite Control Menu. Refer to page 26 of the 430EX III-RT Manual for additional information. Also note that the IR AF Assist Beam is INCOMPATIBLE with Mirrorless cameras. The speedlite will switch to Intermittent Flash Firing. Regardless of speedlite’s Personal Function set to IR or Intermittent Flash Firing. The camera overrides the option set on the speedlite. Note HSS when set will be in effect only when the shutter speed is above flash sync speed. Even if HSS has been enabled on the speedlite. The camera will display an H with a lightning bolt when HSS is active. Also note that Modeling Flash is DISABLED on the EOS R series. To set the speedlite’s settings from the camera body refer to page 40 in the manual. The picture below shows an example of the speedlite’s settings displayed on the camera.

 

[p4pictures]

I agree with what Demetrius mentioned, but want to add that there are two settings that can limit the shutter speed with flash.

In the Flash function settings if you choose to have a fixed shutter speed in the slow synchro setting, then when using P or Av modes HSS is not possible. You can see this if you expand the caution note under the slow synchro settings.

https://cam.start.canon/en/C017/manual/html/UG-03_Shooting-1_0100.html

Secondly, but less likely, if you manually limit the shutter speed to the sync speed or slower, then you will not be able to use HSS. You can find that in the manual at the link below.

https://cam.start.canon/en/C017/manual/html/UG-09_Custom_0030.html#Custom_0030_2-4