5D mkII + 580EXII - Focus assist without flash?

Last night I was out and about with so police doing the rounds of the local nightclubs.

My 35L was sometimes struggling to find focus yet the images at ISO6400 were perfectly useable without the flash.

Is there a way of using the flashes focus assist without the flash firing?

Thanks!
Gel

Hmm,

I know you can set the 580EX II to "master" and not fire the flash. It will give you the ability to use the AF assist and probably still fire the metering flash, I suppose you could just set the flash to manual and it might take care of that.

Gel wrote in post #9739816
Last night I was out and about with so police doing the rounds of the local nightclubs.

My 35L was sometimes struggling to find focus yet the images at ISO6400 were perfectly useable without the flash.

Is there a way of using the flashes focus assist without the flash firing?

Thanks!
Gel

Go into the camera menu and select the External Speedlite control option.
Then select Flash function settings.
In the Flash function settings menu, scroll down to Flash firing and select Disable.

There's no need to go into the Wireless function. As a matter of fact, you do NOT want to set wireless function because if you do, the master will still fire a flash even if the flash is disabled.

PacAce wrote in post #9741031
Go into the camera menu and select the External Speedlite control option.
Then select Flash function settings.
In the Flash function settings menu, scroll down to Flash firing and select Disable.

There's no need to go into the Wireless function. As a matter of fact, you do NOT want to set wireless function because if you do, the master will still fire a flash even if the flash is disabled.

I didn't think the 5D Mk II had that option because it doesn't have a built in flash. (Next time I'll let some one more familiar with the 5D Mk II answerops
(I'll quietly delete my post now.... )

PacAce is right. That's exactly what I do with my 5D-II and 580EX-II If you set this up as one of your C1, C2, or C3 modes, you'll be able to switch between flash functions in a fraction of a second.

msowsun wrote in post #9741194
I didn't think the 5D Mk II had that option because it doesn't have a built in flash. (Next time I'll let some one more familiar with the 5D Mk II answerops
(I'll quietly delete my post now.... )

"external" speedlite control

It is a separate menu item from the onboard control on flash-laden units as well.

Thanks guys, much appreciated. I was finding focus by selecting areas of contrast but it wasn't ideal.

Helps a lot, I love this forum.