How to get my slave to flash ?

First off sorry for posting this tech question in this board.
I want to because alot of folk here use off camera lighting and I think they will understand my question and give a helpfull answer.
Ok, im going to be buying an extra speedlite soon.I am going to get a 580ex
and I have a 430ex already.
I want a 580ex because I want to use OCL using the master/slave control with the IR.
I obviously have to have the 580ex on the cam hot shoe so I can trigger the 430ex slave via IR,but How do I just get the 430ex slave to flash without getting the 580ex on my cam to flash,as I ONLY want the 430ex slave to flash??
Is this possible as I only want light coming from the off cam 430ex?
so how does it work if you dont want the hotshoe mounted 580 master NOT to flash?

Thanks.

I do this quite often. I usually like to use a one light setup and don't like any on-cam flash because it doesn't look nice... for the most part.

What do I do? I zoom the 580 to 105mm, and point it straight at the slave. This will increase your triggering reliability by about 100 times and usually doing this keeps the 580's light out of your picture.

Remember, it is important to point the front of the 430 towards the 580... so tilt or swivel the head however possible to get the front to face the 580.

Thanks Lloyd. Yeah I understand having to point the 430 towards the 580 to get the IR to work.
Wat do you mean by zoom the 580 to 105mm?? the lens focal length??

maytownme wrote in post #4057804
Thanks Lloyd. Yeah I understand having to point the 430 towards the 580 to get the IR to work.
Wat do you mean by zoom the 580 to 105mm?? the lens focal length??

You zoom the flash head to 105 MM to get a narrower more concentrated beam. Your flash usually does this automatically when it's directed forward.

maytownme wrote in post #4057804
Thanks Lloyd. Yeah I understand having to point the 430 towards the 580 to get the IR to work.
Wat do you mean by zoom the 580 to 105mm?? the lens focal length??

On the top right corner of the 580 and 430 ex is a zoom button. You hit that and the zoom value should start flashing. Then you turn the wheel (or press the buttons on the 430) to set your zoom value. This will zoom the flash head so less light is wasted for longer focal lengths. If you set your zoom to 105, it will be a more concentrated beam of light rather than a huge flood of light. This will throw light further, and therefore, increase the chance of the 430 reading that light to slave off of. Also, because it's a tighter beam of light, it'll help keep the 580's light out of your picture.

Thanks guys. So thats how you do it with the master slave setup.

Also, keep in mind that slaves usually default to 35mm zoom setting. You wanna evaluate your scene and decide if this is the proper setting, because in slaving, you'll have many areas lit and many areas NOT lit... something you don't really have to think about in on-cam flash.

Can't you go into the custom functions of the 580 and set it 'not to fire'...and still have it trigger the slave?

Big Mike wrote in post #4057953
Can't you go into the custom functions of the 580 and set it 'not to fire'...and still have it trigger the slave?

Never tried this as the actual flash itself aids in transmitting the master/slave commands.

There is actually a setting on the 580 that makes it only fire to set off the slave, not effect the exposure. You hit one of the buttons (the zoom maybe, I don't have it in front of me right now), until the graphic displaying light coming out of the front of the little graphical 580 on the lcd screen starts to blink. Then you turn the little control wheel to Off (the graphic displaying light coming out of the front of the little graphical 580 on the lcd screen will disappear).

You know what? now that you mention that, jamie, I remember trying and wrestling with that for ages and could never get it to work. either I'm stupid or my 580 isn't working correctly, because it ALWAYS fired into the exposure no matter what...

I think if you are too close it will still affect exposure - since there's a minimum amount of light required to trigger the other flash...

On the 580ex II you can easily just turn the flash off and trigger the slave. However, I never tried it with my 580ex I.

Yes there is a setting on the 580 that turns the flash of and it still flashes but thats only to send info to the slave, It does not affect the exposure.
Turn on the 580 - set to master - press zoom once - turn dial to switch off flash.
The 580 will only send info to the slave via a low flash output

Hmm, I could never get that to work.

Anyhow, I like to use higher powered flashes... it really helps in sunlight. A low power flash probably wouldn't cut it.