Got a 2nd 580EX, now what?

On a whim and pretty good deal, I got a 2nd 580EX. I figured it was portable and hoped they would "talk to each other" better.

I dislike the odd shadows of the on-camera flash and had noticed the built-in slave communications.

Both flashes have sto-fen diffusers and I have a monopod and tripod.

My subjects are environmental portriats.

I'm not opposed to getting other equipment, but want to keep it pretty portable and easy for 1 person to manage.

I'll pour over the manual, keep reading these posts, and experiment, but I'm feeling a little lost. I'd love a dummies book that spells it out simple-like - or a few simple pointers. Thank you all.

Since you have 2 now, you can do a nice little 2-light "studio" setup with some cheap umbrellas.

I also have 2 580EX's now but I don't think I'm going to use them together in a studio setting since I have the B1600...unless I can figure out how to work the slave/master deal in manual instead of E-TTL.

There are two ways to work the 580EXs in manual mode in a master/slave config. And neither is that hard to set up.

In the 1st method, you control the master and slave power outputs from the master. The master is set to manual mode and the slave is set to ETTL mode. Set the slave as B (the master is always A). Set the master output power, then set the slave output power, both from the master flash. See page 42 of your 580EX manual for specifics.

In the 2nd method, you set the individual flashes to manual mode and set the output power of each flash via the individual flash controls. See page 43 for specifics.

Ahh I see. I'm retarded. I just wasnt holding "Mode" down long enough on the slave. I thought it was locked into E-TTL. hah.

You don't have to do anything on the slave. Just turn it on and set the switch to slave. The master controls everything. If you set the master to M it sets the slave to M also. All power settings are controlled from the master flash.

Another question if I might - if you are using the two 580s in manual wireless mode in conjunction with the B1600 will the 'communications' flash between the two 580s trip the B1600?

They talk using IR - not flash

To the OP:
Off camera flash is the key light
On camera flash is the fill

Use the sun for hair/rim - kickass stuff.

If you bring a stand with an ubrella to soften the key light.

Right but the ETTL preflash will trip the B1600 prematurely. I assume if you use the EX flashes in manual mode this won't be an issue but I've never tried it myself.

ex in manual trips em. use manual, it might take a little to get the hang of, but worth it in the end. personally i dont trust ettl, i dont feel 'in control' .

p.s.. I'm seeing a doctor about this control thing.....

As long as the speedlite flashes are in wireless remote config, there will be a "preflash" (it's actually a command flash which is distinct from the real preflash used for ETTL metering) that will fire an optically triggered slave, regardless of whether the speedlites are in ETTL mode or manual mode. The best thing to do when speedlites in wireless remote config are mixed in with other strobes is to fire the strobes via a sync cord or radio remote. In other words, don't use optical triggering with them.

As for the comment about the speedlites using IR to communicate and not flash, that's not exactly a true statement. The only reason IR is involved here at all is because there is an IR filter in front of the sensor on the slave that "sees" the master commands to exclude extraneous lights. But the master, if it's one of the speedlite flashes and not an ST-E2 transmitter, uses the visible light (which also contains the IR component) from the flash itself to send out commands. There is not a seperate IR transmitter used specifically for sending out the master commands to the slaves. The ST-E2 is basically a mini flash with an IR filter placed over the front of the flash head so that only the IR light gets emitted by it.

Leo, do you know if a technical resource from Canon that outlines exactly how the master/slave setup on EX speedlights works?

If there is such a source, I am not aware of it other than Mr. Chuck Westfall himself. But even he has restrictions on what he can and can not tell the general public about Canon products and how they work.

It may be true and by all means I am no expect and can't back it up with any documents.

But from engineering standpoint - why would canon do this?

It's easier to put an IR emitting diode behind the red plastic on the 580.

The Xenon tube would have to fire probably 4+ times to communicate what it needs to the slaves.

But then who knows... canon does have slow sync and can fire their flashes at low output with very high frequency.

This should be simple enough to test. Cover the red AF focus assist light panel and the IR receiver panel with black tape and see if wireless remote still works. Do the same by covering the flash head and see if wireless remote works.

The reason Canon would use the flash tube instead of an IR LED is simply because the tube would give you a greater working distance and a wider angle of coverage than a small LED would.

Thanks Leo, that's what I thought. I know that if you turn off the master flash function and use it as a master in the master/slave mode it still flashes to communicate with the slave. I was fairly certain this could trip the optical slave on the B1600.