Help with 20D Flash

In MF mode when i press and hold the shutter button half way down the flash lets out bursts of flash and then stops and then I can take the picture.

As I am new to Digital camera's and the 20D I was playing with the settings and not to sure what I have done to make the flash go like this.

Could someone help me with ideas how to fix this.

In AF mode its OK the flash works fine.

Thanks in advance

The camera does that automatically to help in focusing. I assume when this is happening is in lower light situations?

Yeah tonight is the first night that I have used the camera and was freaking out as when i used the flash during the day it was fine.

But like a boy with a new toy I have been playing with the settings and found the flash going off .

It is pretty dark in here so maybe that why its going off

Thanks for your Help

Man this is my 1St SLR Digital and Love it.

Do you know any good sites to teach me about the ins and outs or using this camera

You can turn that off in th Custom Functions. You have three options:
1. AF Assist with internal and external flash - default
2. AF assist only with external flash, internal (flash bursts) turned off.
3. AF assist turned off.
Scott

Mate i went into custome functioins and cant see the AF you mention above to turn off the pree falsh before flash.

Sorry to sound like a bummy but today is my 1st day with this great CAMERA

CFn. 5 is to control the AF Assist Function.
This has nothing to do with Pre Flash which occurs when you fully depress the shutter button or when you press the FEL button. The 20D and 10D use the on camera flash automatically in low light as an AF assist lamp by putting out a series of pulses of light. On an EX Series Flash, this is done via the lamp under the red plastic. AF Assist occurs in low light when you 1/2 depress the shutter button. This is different from the pre flash which occurs when you fully depress the shutter button. Just before the actual flash (milliseconds) the preflash fires followed by the flash. You won't see the preflash unless you hit FEL or are in second curtain sync flash. When you use Manual flash, the preflash is turned off.
Scott

I'm a bit confused...

It was stated that in MF mode (manual focus) the flash let off a set of bursts on pressing the shutter button half way down, but in AF mode(auto focus) it was OK.

Should this be the other way around, burst in AF and no burst in MF?

Yes.

Sorry mate yes its in Auto Focus when the flash set off with a burst of light before the pic is taken with a single flah

You will also get pre-flashing when you set 'red-eye' reduction, which I find a nuisance as the subjects think it is the actual flash and start to move !

See if you can find a 420EX flashgun on ebay or similar. It's much better than the internal flash and will stop those irritations....

Please read the post above. That is not preflash. That is the AF Assist function of the flash. You can turn off the AF Assist function of the flash by using CFn. 5 on the 10D. Preflash occurs milliseconds before the actual flash to determine how much flash to put out, It doesn't occur until you fully depress the shutter button or hit FEL. You will not normaly see a pre flash unless you use FEL or are in 2nd Curtain Sync. Red Eye Reduction is also not pre flash and isn't carried out by the flash at all. It is carried out by the Red Eye Reduction Lamp on the body of the camera. You can turn it off in the Menu. PreFlash is only one thing. It is the burst of light sent out by the flash either on camera or speedlight just prior to the flash. It is used by the camera to measure how much flash output is needed.
It's one thing not to read the manual, but it's another thing not to bother reading the answers in the thread you are posting to.
(Sorry about the Bold, I just had to get that off my chest )

Understood scottburgerphoto, those of you from Brooklyn are known to be 'Lippy"! As far as I am concerned any flash before the main one can be termed pre-flash. My original post stands.

You are entitled to your opinions. However, correctly used, the term "preflash" has a specific meaning, and that is the light that is emitted only in the fractional second before the main flash, and it really does not have anything to do with redeye or focus assist.

Scott was simply directing you by the conventional usage.

---Bob Gross---

If I was "scottburgerphoto" I might take offense at your characterization of people from Brooklyn as being "Lippy".
The real point as Bob Gross pointed out is that certain terms like Pre Flash have very specific definitions. When you assign those terms your own definition they lose their meaning. It confuses people trying to learn and serves no useful purpose. So your post may "stand" as you say, but it does so alone and talking to itself because no one else knows what it means.

The answer to the original poster's question is on the page. There is nothing further to be gained from this thread.