Speedlight 580EXii not using infrared focus assist in manual mode on canon 5dmrk3

[JamesDonohue]

Hi, I can't for he life of me figure out how to activate the infrared focus assist (for focusing in low light or no light environments) for the Canon Speediest 580EXii while mounted on the Canon 5D mrk3 while in M (manual) while using the camera photography. I'm usually going night events that demand focus practically in the dark, but I just don't use Automatic settings If anyone has any thoughts on the matter, I'd be thankful to hear them. Mr. Donohue

[cicopo]

I don't have any 5D's but generally every body I have had used a menu item to either turn that feature on or off. Worth checking your manual.

[tnicoson]

See Page 98 of the CAMERA Owner's Manaul for enabling the AF Assist Beam, but note the precaution at mid-page that the AF Assist Beam must be enabled on the FLASH UNIT as well as on the camera.  On the 580 EXII, this is done with Custom Function Number 08 (CFn-08).  See Pages 27 and 28 of the FLASH UNIT Owner's Manual for instructions on this.

Good luck !

Regards,

Ted

[RexGig]

Is the AF set as Single Shot? The AF assist light does not work in AI Servo.