580EX II not recognised on 5DS/6DII, but ok on 5DI

Hi all.

Anyone have an idea here? My trusty 580EX II gets a lot of use with its High-speed sync, I've used it with the 5DS plenty of times. But now for some reason it's not recognised, neither on my partner's 6DII. In the Speedlight options in the camera menu it comes up "flash incompatible or power turned off". Clicking on the H-button on the flash produces no such option. I can still shoot ETTL up to 1/200s.

Only when I mount the flash to my 5D Classic, then I'm able to click the H-button and see it activated on the display, and I'm able to select speeds faster than 1/200s.

Batteries are good.

Any ideas?

My guess is there is something wrong with the flash. I don't have a 6D II but I just tried my 580EX II on my 5D4 and high speed sync works fine.

Bob

[No message]

It should work - I had an old 430 EX (original) that worked on my 6D ii. Note that not all the features were available on the old flash that may be available on a newer flash - from memory some menu options were greyed out.

Colin

haha the most simple solution worked! Why didn't i think of that? Thanks cjb

And double check it's fully engaged in the hotshoe. That the 5D I recognizes it argues against a speedlite fault and for a connection issue.

IMHO

Edit, d'oh! too slow. Glad you got it sorted.

--
Unapologetic Canon Apologist