On the Rebel you go to 'settings2' then 'custom functions' then 'AF-assist beam'. I think the 10d and 20d menus are different though. Greg > -----Original Message----- > From: owner-photoforum@xxxxxxxxxxxxxxxxxxxxxx > [mailto:owner-photoforum@xxxxxxxxxxxxxxxxxxxxxx]On Behalf Of > lea murphy > Sent: Wednesday, January 25, 2006 11:38 AM > To: List for Photo/Imaging Educators - Professionals - Students > Subject: Re: building a studio at school > > > I think the flash idea to act as a slave trigger is a great one and > cheap to boot. > > Greg, how do you turn off the preflash? Mine may be off by default > since I've used the little module without any problems. Hmmmmmmm? > > Lea >