550ex and pre-flash triggering something else?

[hawk911]

I did a search, and it looks like the problem using a 550 is the pre-flash will cause the slave to fire before the shutter is openunless done in manual mode. Is there a setup where I can use my 550EX to trigger a decent, but cheaper, slave unit? I have access to a buddy's Hanimex TZ855 and I wonder if the same pre-flash trigger will happen. I'm looking to buy a second flash unit; hence the question.

[cosworth]

You have to use it in M mode or buy a Canon flash that will slave. "Digital" slave eyes are spotty at best and I have yet to hear of one that ignores the preflash properly. Plus they are half the price of a used 430ex...

[hawk911]

So I have to use my 550 in M mode then also?

[PacAce]

So I have to use my 550 in M mode then also?

Yes, but I thought you understood that (based on what I read in your first post). Or were you referring to the camera being set to manual mode in your first post?

[hawk911]

well, let's say I don't understand the flash in manual mode. I'll have to read the manual, and try some things quickly.

[Curtis N]

well, let's say I don't understand the flash in manual mode.Start with the head pointed straight forward with no diffuser, so you have a distance scale to guide you. Adjust the flash power, aperture and/or ISO until the distance scale gives you a reading that resembles your subject distance. this will help you understand the basic relationships involved. Then you can add a slave, bounce or diffuse, whatever. You'll loose the distance scale but with a little trial and error, you'll figure things out.

[hawk911]

Curtis, that almost made sense. I'd like to use the 550 on the camera, and a second unit on a stand, triggered wirelessly (optically triggered). Hope I can repeat the terms well enough to help folks understand. Does this change anything that you said?

[Titus213]

The 550EX in manual mode will trigger an optical slave for another flash. Basically the manual mode on the 550EX eliminates the pre-flash. It works well but you have to figure out the power needed from the flash units since you lose all automation with the camera. I just did a test run with my 550EX on camera tripping my Sunpak 555 with an optical trigger. A meter would be a big help to you.

And this is one reason my second flash that just arrived yesterday was a 430EX.

[hawk911]

I'm missing the link between the 430 and the 550. Can the 550 trigger the 430 with no pre-flash junk?

[cosworth]

Yes, manual mode works for Canon's master/slave function.

I think an in-depth read of the EOS flash bible is in order. See the sticky at the top of the sub forum.

[hawk911]

Reading now. Thanks. Looks like I should consider another EX model, where I can dial the power up/down.

[Titus213]

I'm missing the link between the 430 and the 550. Can the 550 trigger the 430 with no pre-flash junk?

There is still a communications flash but in a two flash setup the 550EX and 430EX talk in Canon speak so the pre-flash is of no consequence. All ETTL functions are preserved for full automation with the cameras. And it was only one reason I bought the 430. Another was that my wife likes to take flash pictures with her Rebel in as simple a mode as possible - that's ETTL.

Is there some other reason you don't want a pre-flash?

As a plug for the 430EX, I was amazed at how small it is compared to my 550.

Now to figure out ETTL...:lol:

[hawk911]

Nope- I'm fine with pre-flash as long as the slave isn't triggered prematurely. I just wasn't looking for a pricey solution like the 430; the cheaper solutions seem bothered by pre-flash.

[PacAce]

Nope- I'm fine with pre-flash as long as the slave isn't triggered prematurely. I just wasn't looking for a pricey solution like the 430; the cheaper solutions seem bothered by pre-flash.

I think the 430EX being thrown into the discussion kind of confused you. If all you want to do is use your 550EX to optically trigger the Haminex, then you need to set the 550EX to manual mode. This is done by pressing the Mode button on the 550EX repeatedly until the LCD shows "M" instead of "ETTL" or "Multi".

But, to use the 550EX in manual mode, you will need to adjust the power output of the flash manually, too. If you want the 550EX to contribute lighting to the picture, you'll need to determine what power level you're going to need from the flash. You can determine that by trial and error shooting a couple of test shots and adjusting, by using the flash-to-subject distance as Curtis described above, or by using a flash meter.

If you only want to use the 550EX to trigger the strobe without actually contributing any light, then just set the power level of the 550EX to the lowest it'll go which, I think, is 1/128.

Hopefully, that clears that up for you. :)

[hawk911]

right- the 430 kind of threw me. I guess what I wanted was a matrix that said the 550ex can trigger x, y, or z flash units, and here's the respective known price for each. I haven't done manual on the 550, but the mechanics of it sound simple enough. The execution will yield how simple it really is.

In my scenario, I'll be using the 550 as fill for people in the front of the frame, with the slave lighting a car positioned as BG. I just wanted the slave to light the car so nothing is lost. I'm still not sure if we'll be doing portraits, so this may be somewhat mute in the short term. Long term, I'd like to get studio lights to really do lighting well. The speedlights allow me more portability for the outdoor shooting I do.

[Titus213]

Sounds like you can invest in an $80 Sunpak 383, an optical slave, and a $200 light meter to get the two lights where you want them...

or...

Spend $240 on a 430EX and use the automation (which works much of the time but not outdoors).

There are not a lot of inexpensive options that I know about.

[hawk911]

and they don't work outdoors because of the bright sun interfering with the flash signal?

I may have a 550ex for $200- sound like a good compliment to the existing 550ex?

[Titus213]

I would suspect that is the reason...I have tried it and not had a lot of success.

550EX for $200 would be a tough call for me. Have you checked this link?

http://photonotes.org/cgi-bin/flash-lookup.pl?flash1=canon550ex&flash2=canon430ex&flash3=canon580exii

[hawk911]

I pulled the trigger on the 550. I like the one I have. Outdoors, I don't expect I'd be more than a few feet to 20 feet away, if that far. We'll see.

[PacAce]

I pulled the trigger on the 550. I like the one I have. Outdoors, I don't expect I'd be more than a few feet to 20 feet away, if that far. We'll see.

Look at it this way, outdoors, an optical slave trigger would probably have been iffy, too, anyway. :)