EOS M how to get external flash to fire

[p27159]

I asked this question lumped together with several other questions, but was afraid it might get lost in the shuffle so I’m going to ask again.

I am looking for information specific to the EOS M model.  I have seen some things online, but not specifically for my model. The user manual was of no help.  I can plug my flash into the hot shoe, and turn it on, and it lights up when it’s fully charged and ready to fire.  However, no matter what settings I’ve tried, and making sure I’m in a very dark closet to test this out, the flash never fires.  For right now, I’m just looking for a mode with a flash with fire for every picture I take, and then I can worry about the flash firing only if it detects it’s necessary.  I’ve played around with the camera, both in automatic and manual modes, and with the INFO button, I can scroll over to the lightning bolt icon, and it doesn’t have a slash through it, so it looks like it’s enabled.  If anyone can give me any ideas of why it might not be working and what I can do to fix it, would be greatly appreciated,

[p27159]

Brian, thank you so much for all the time you’ve taken to respond to my comments.  I had already placed an order to have a small flash device delivered, as I said, it claimed it was a compatible device, but not made by Canon specifically. It just arrived, and I attached it to my camera, and as discussed previously, that menu option Doesn’t work with it, but I was able to get it to successfully work.  Therefore, I think this issue is now closed, unless you have any other further remarks. Thanks again for all the help you’ve given me, it is really appreciated.  I think it’s amazing that people like you post on these boards in your own time with no compensation, just to be helpful.

[deebatman316]

3rd Party compatibility is up to the 3rd Party manufacturer when it comes to flashes that talk to the camera for autoexposure. All Manual flash units are usually compatible. All they need to work is a signal from the camera to fire no other communication is needed. Once autoexposure comes in then compatibility can be hit or miss. Usually 3rd Party flash units are made to be compatible with certain brands. Every manufacturer implements their own flash protocols differently. Canon's E-TTL flash system is NOT cross compatible with Pentax's (P-TTL flash system), Nikon's (i-TTL flash system) or Sony/ Minolta's (ADI/ pre-flash TTL flash system). Manual flash units are manually set that's why they're compatible with all brands. Once flash autoexposure comes in its a much different story.

[p27159]

Demetrius, thanks again for your comments, which make perfect sense to me. I also want to thank you for taking the time to be so helpful on a forum like this!

[deebatman316]

You can use any Canon EX Series speedlite or EL-1 & EL-100 speedlites. Just avoid very old film era Canon speedlites those usually end in E/ EZ/ G & TL. These speedlites use a different and INCOMPATIBLE flash system designed for film cameras. You don't have to get the newest Canon speedlite for your camera. Older Canon EX series speedlites are compatible but the in camera flash menu is NOT COMPATIBLE with older speedlites. They'll show the same "Incompatible Flash" message but this should be ignored. The flash is still working correctly it just doesn't support the new 2 way flash communication that was added in 2007. Older flash units will have to have settings changed directly on the flash itself. Also the camera will show items grayed out or missing when looking at the flash settings menu. The picture below shows what happens when an older Canon EX series flash is mounted in the hot shoe. In this case I had the Canon 550EX mounted in the hot shoe. The 2nd picture is a picture of a newer flash unit mounted in the hot shoe which is a Canon 600EX II-RT. All settings are settable from the camera with newer speedlites. I own a mix of old and new speedlites and they all work as designed. 

Flash Function Settings screen