AF assist led

[nkhoo]

Hello ppl, i just bought a 580ex and i was wondering, is there anyway for me to shoot with the af assist activated but the flash don't fire?

I noticed that with the af assist led, my cam focus a lot faster and more accurately esp in low light conditions. But there are times when i would like to capture the ambient light without using the flash to spoil the mood. So is it possible to use the af led without firing the flash?

Thanks.

[sumball]

Turn the flash head around 180deg?

[nkhoo]

But if i turn my flash head around, the flash will still bounce off some wall. Covering my flash head is also not viable, my flash will be firing at full power each time i take a shot if set at ettl. I can cover and set it at 1/128 on M mode, but batt will still be wasted. Is there anyway to "turn off" the flash without turning off the af led?

[drumma]

i think u can. or at least i remembered doing something like that. have u read the manual?

[Splutter]

Yes it's possible, I can't rem if you have to set it on the flash or on the body though.

[nkhoo]

I've read through the menu for the flash but it didn't say anything about turning the flash head off while keeping the af led on. I'm using a 400D, i'm not sure if there is a function on the cam for that. Can anyone help?

[raptor84]

There should be a custom function to disable flash on the body..

[+evenstar]

change to MASTER mode, and turn off the unit firing mode.

do note that pre-flash will still fire though, but the actual flash will not.

[tpchsg]

Write to Canon Singapore. I have tried that for other matters. They are very responsive.

[dreamtheatre]

in your custome function on the body. RTM.

[tpchsg]

Originally Posted by dreamtheatre in your custome function on the body. RTM.

I could be wrong, but I doubt 400D has that function to disable the flash.

[nkhoo]

Thanks for the advice guys. The 400D does not have a custom function to disable the flash head. The only way that seem to work is to use the wireless flash on the flash gun by setting it to master and disable the flash head.

[dreamtheatre]

actually, the alternative is to get the flash transmitter....but $$$$$

The thing is, even with the AF assist beam attached, it will only activate below a certain threshold of brightness. It wun be a 'full time ON' thing. So if you get into situation where the light level is at the border where the AF sensor 'thinks' it can aquire a lock but the light is just a tad too low for a fast AF operation, then that's where all the 'trouble ' is. The AF will TRY i's best to lock-on, and the body does not send out the signal to ask for 'help' from the AF assist.

Maybe future EOS models will have a CF to set AF assist beam to 'always on'. Let the user decide.

DT

[+evenstar]

AF assist beam is activated the moment the flash is on...even in daytime..

[Belle&Sebastain]

guys i notice something on my transmitter, ST-E2, each time i use it my shots always underexposed itself, both on the 20D and 1D. i will send it to canon to investigate and share my findings with everyone in march.

[dreamtheatre]

Originally Posted by +evenstar AF assist beam is activated the moment the flash is on...even in daytime..

funny, my EOS 300, 30 and 1Ds all have AF assist only in dark condition. When ambient is brigt enough , it does not activate -- regardless if the 420EX or 550EX is mounted.