Any fix for the M5 shutter lag when external flash is mounted to it?

Been searching around for a fix but im guessing there are none. When I shoot normally in low light situations that would require a flash, it shoots normal, fast (as fast as the shutter speed i set it to of course). Once I mount my 600ex on top of it, the screen would brighten up like crazy and pressing the shutter button down makes the camera hunt and focug for some 3-5 sec, then after it will take the pic! Ive never experience this slow in a camera. whats up?

must say I've not used an external flash on my M5 before - just tried a 580ex inside at night with only a 100w light in the room without any of the symptoms you've described.
Probably need more info - what mode are you using? what sort of ISO/speed/aperture?

Hmm weird. F2.8, Shutter 100, iso1600, manual, ef adapter to a 16-35ii
Must be some setting I have turned on or something. Flash on ettl. It was dark enough here to warrant that focus loght turning on on the camera

Something about low light that causes it to be super slow. I'm in a bright place now and it's fine.

Is it possible that the focus assist light is turned off?

its on but that shouldnt matter as there is red beam assist coming from the flash? I dont know. This is a bit odd

Found a thread on dp on this: https://www.dpreview.c​om/forums/thread/41006​87

I have the same problem. Im a pro photog and bought this camera for back up. Tried everything. Manual focus, turned off all view finder preview. Ive even had the camera replace. I love this cameras features and image quality but cant get the shutter to fire when flash attached. Hope there’s a fix.

eugenekamphoto wrote in post #18551453
I have the same problem. Im a pro photog and bought this camera for back up. Tried everything. Manual focus, turned off all view finder preview. Ive even had the camera replace. I love this cameras features and image quality but cant get the shutter to fire when flash attached. Hope there’s a fix.

can you let us know what flash you've tried?

Long shot but do you have second-curtain sync enabled?

So, to stimulate a bit of thinking by the folks complaining about the M5...Is the problem specifically associated with

1. low light only, or
   
2. flash attached only, or
   
3. low light + flash attached
   

kaitanium wrote in post #18343709
Found a thread on dp on this: https://www.dpreview.c​om/forums/thread/41006​87

I do note in that thread that Hebalers, down near the bottom, said "It happens at low light when you have a flash attached set to TTL." I believe most recent EOS cameras work best with E-TTL, not TTL. Of course that could be a typo.

Canon DSLR cameras only have E-TTL metering, the older film cameras have E-TTL and TTL to allow them to be used with both "new" and "old" flashes. Older Canon flashes from before the Speedlite EX series only provide TTL flash, not E-TTL.

I do note however, that you say you are using E-TTL. Might be worth verification that C.Fn 05 (on the Speedlight) is not set to 1.

Another thread at https://www.dpreview.c​om/forums/thread/41138​45 has quite a discussion. Go to page 5 and read the remarks about the Exposure Simulation setting. Some people found improvement with it Enabled.

And at https://www.dpreview.c​om/forums/thread/40962​18 somone quotes a Canon resource

"Thank you very much for your EOS M5 inquiry.

Regrettably, we must tell you that this camera model actually has a higher shutter lag in a dark environment when shooting with a flash, even in a completely manual mode when the shutter button is pressed down completely. This is constructive and can not be changed.

We apologize for any inconvenience, and we apologize for any inconvenience.

Best regards,

Anke Hunter
Canon Services & Support"

John from PA wrote in post #18552032
And at https://www.dpreview.c​om/forums/thread/40962​18 somone quotes a Canon resource

"Thank you very much for your EOS M5 inquiry.

Regrettably, we must tell you that this camera model actually has a higher shutter lag in a dark environment when shooting with a flash, even in a completely manual mode when the shutter button is pressed down completely. This is constructive and can not be changed.

We apologize for any inconvenience, and we apologize for any inconvenience.

Best regards,

Anke Hunter
Canon Services & Support"

Did Canon once again shoot themselves in the foot with something not done properly in connection with use of flash?!

Wilt wrote in post #18552048
Did Canon once again shoot themselves in the foot with something not done properly in connection with use of flash?!

What was the prior?

musicmaster wrote in post #18552179
What was the prior?

1. Back in the days of the 20D and 30D, folks had to somewhat permanently crank in FEC = +1 in order to get eTTL to illuminate the scene to the same tonal values as would be achieved with ambient-only lighting. (Then suddenly, with the 40D, this corrective flash value ceased to be needed.)
   
   
2. Although eTTL works properly with pointing the flash head upward to bounce illuminate exposure, eTTL flash automation does not seem to work properly when you put the flash into a softbox, for direct or indirect illumination.
   
   
3. With the 580EXII, with the addition of the 'External' mode (flash photosensor Auto mode) would underexpose a scene by 1EV-2EV, compared to photosensor autoflash results with other brands of flash.
   
   
4. Then with the 70D, there were complaints of bounce flash underexposure not experienced with other models of Canon dSLR, which went away in the 80D.
   

Wilt wrote in post #18552202

1. Back in the days of the 20D and 30D, folks had to somewhat permanently crank in FEC = +1 in order to get eTTL to illuminate the scene to the same tonal values as would be achieved with ambient-only lighting. (Then suddenly, with the 40D, this corrective flash value ceased to be needed.)
   
   
2. Although eTTL works properly with pointing the flash head upward to bounce illuminate exposure, eTTL flash automation does not seem to work properly when you put the flash into a softbox, for direct or indirect illumination.
   
   
3. With the 580EXII, with the addition of the 'External' mode (flash photosensor Auto mode) would underexpose a scene by 1EV-2EV, compared to photosensor autoflash results with other brands of flash.
   
   
4. Then with the 70D, there were complaints of bounce flash underexposure not experienced with other models of Canon dSLR, which went away in the 80D.
   

I (only somewhat tongue-in-cheek) have speculated that Canon puts brand-newly hired engineers just graduated from engineering school on the flash team, and then once they really know what they are doing, they are moved out from the flash department into lenses and bodies.

Honestly, this sounds like a lot of issues that could be corrected via software/firmware updates. It's surprising they don't somehow address these issues.