09-02-2013 02:44 PM
09-02-2013 04:28 PM
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.
09-02-2013 10:22 PM
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 !