No AF beam assist on 5D MK II and speedlite 580 ex II in camera manual mode

[carbonatd]

Hi,

I have a 5d MK II and a Speedlite 580 EX II that have worked great for years.  While shooting a wedding the other day, my AF beam assist from the 580 stopped working while the camera is in Manual mode.  In the camera, I have the AF set to 'One Shot'.  On the flash I have C.fn 8 set to '0' (enabled).  Still no beam assist.  I've reset both devices to factory settings (in which beam assist is on by default) and still no luck.

The 580 does provide beam assist while on a 7D in manual mode, and the beam assist actually works on the 5DmkII while the camera is in full auto mode.  Everyone suggests to check the AF mode to make sure it's in 'One Shot', and I can promise you it is.  I have even switched to AI Servo and then back to One Shot, to see if the camera is 'stuck' in the AI Servo mode for what ever reason.

At this point I becoming incredibly frustrated as everything is supposed to work in default settings, and I have wiped all of my custom camera functions in hopes of getting this to work.  I don't believe this is connection related, as the flash works on the 5dmkII in auto mode.  Does anyone have any suggestions for anything else I can try?

Thanks

[carbonatd]

Just tested my 5d MK II with a 430exII, and the problem still exists.  I've tried cleaning the hot shoe contacts, but I am not inclined to believe it is a mechanical failure, due to the fact that the AF beam fires when the camera is on full auto.  Any suggestions before I switch to Nikon?

Thanks

[diverhank]

Did you check the camera C-Fn III-5, AF assist beam firing to see it is also enabled? 

[carbonatd]

This function is enabled by default. I have reset the camera to factory defaults, which has this setting enabled. Also, as a global setting, wouldn't this prevent AF assist from working with the camera on full Auto mode? The speedlite does produce a beam while the 5dmkii is in full Auto

[jrhoffman75]

Have you verified that the CF is disabled?

Resting camera settings doesn't always clear custom functions. AUTO  also often overrides custom functions. 

[maartjevanrijs]

Hey, so this is a very old post, but. This is exactly a problem what is happening ti me today. What do you mean by CF? Sorry, im literally desperate

[diverhank]

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@carbonatd wrote:
This function is enabled by default. I have reset the camera to factory defaults, which has this setting enabled. Also, as a global setting, wouldn't this prevent AF assist from working with the camera on full Auto mode? The speedlite does produce a beam while the 5dmkii is in full Auto

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Dangerous assumptions on both counts :).  

1. Camera will not reset everything when you reset. It would be a simple matter to verify it.  Also if you access your manual mode via one of the Custom buttons (C1, C2, C3), whatever it was saved there will remain after factory reset.

2. On full auto mode, the camera ignores ALL users' settings.  That's why it would work there.

[carbonatd]

Wow.  You guys are great!  Thanks so much for this.  I just checked, and beam assist was disabled!  I am kicking myself now.  Nobody to blame but my own fat thumbs.

Thanks so much guys!  If you're ever in the Monterey area, let me buy you a beer!!

[carbonatd]

I must have disabled it while shooting the Milky Way last week.  Why is it right next to mirror lock up??  At least now I know!!