AF Assist Beam

[MDJAK]

This evening, after sunset, I was attempting to take photos with my 1 series, first with my 70-200 F2.8 IS, then with my 17-40 F4.0, then 24-70 F2.8L.

It was quite dark and I was also using my 580ex speedlight.

I'm quite sure the assist beam was not working.

Can someone explain why?

Thanks
Mark

[CyberDyneSystems]

AF assist beam only fires if you are in single shot mode... it won't trigger in AI servo...

Seems odd at first,. but think about it and it may start to make sense.

[MDJAK]

I was in one shot mode. Is it possible it was firing and was just not enough aid? I was only five to ten feet away and sometimes closer.Could it be a custom function? I couldn't find one.

[tim]

With the 20D there is a custom function to turn the assist beam off, CF5. Lens must also be in AF mode (made that mistake once, bumped the AF switch). The camera might not emit if it thinks there's enough light too, but that's just a guess.

[CyberDyneSystems]

I think there is a CF as well... but I thought the default was "on"

But your not actually sure it wasn't firing from the sound of it.. so why not check to see if it is,. or if it isn't before we pursue this any further... we could be chasing our own tails if in fact it is firing :lol:

[MDJAK]

I just found in "personal functions" that the AF-assist beam is turned off. I can't seem to figure out the correct sequence of buttons to push to turn it on. And I just cleared the personal functions and it is still set to off.

There is on and off as a choice and I can't seem to highlight either. Are they tied to something else?

It is definitely not firing. I just went into my darkened hallway and faced a mirror. I would have seen it.

[PacAce]

I just found in "personal functions" that the AF-assist beam is turned off. I can't seem to figure out the correct sequence of buttons to push to turn it on. And I just cleared the personal functions and it is still set to off.

There is on and off as a choice and I can't seem to highlight either. Are they tied to something else?

It is definitely not firing. I just went into my darkened hallway and faced a mirror. I would have seen it.
The personal function you are referring to is to disable the focus assist light. This function is enabled by going into EVU camera settings and turning it on there. By default, it is off, so what that means is that AF assist light in NOT disabled. There is no on or off as a choice because this option was not turned on in the first place.

So, if your AF assist beam is not being emitted (you can tell by just pressing the shutter button half way while looking directly at the flash..no need to look through the viewfinder and a mirror) and you're in single-shot mode, then maybe the flash is broken.

[CyberDyneSystems]

Oh,. it's a "PF" Personal functions need to be set via software tethered to your PC...

Best to crack open the manual at this point :)

[MDJAK]

The manual isn't much help.


What do you mean by EVU camera settings? I've never controlled the camera via computer. I think I screwed that up in the beginning by reversing the order, that is, I attached the camera to my computer before loading the software and now the computer doesn't recognize the camera, so I use a card reader instead.

EDIT: I just saw the personal functions in the manual and see what you mean about being able only to turn it off. I'll have to do further investigation.

Thanks for helping.
mark

[MDJAK]

Well, me, the dummy, figured it out. Shame on you experts. (j/k)

I had it turned off in the custom functions of the flash. Custom function 12.

And as far as referring me to the manual, you guys are my manual.

Thanks again. It's off to B&H for a tripod and head.

Mark

[DwightMcCann]

Well, this thread just saved me a few hours ... won't work in AI Servo mode, eh? No wonder the darn thing wouldn't work last night. BUT, next time I'll be ready! :-)