best optical slave for outdoor use with Canon EOS 540ez...shooting skateboarding

Hello,

I am using a 540ez flash on a eos a2 body. I also have a few other

non-canon flashes that i use on wein optical slaves. However, i

would like to use my 540ez on an optical slave also, seeing how its

the most powerful and have some things i want to try.

Question

I need a optical slave that will work well in sunlight and indoor

use, doesnt have to be one of those ttl ones, has a fairly far

range, and so on. Just a good outdoor optical slave for the 540ez,

because the wein ones dont work on it.

thanks a bunch!

jeff

Jeff,

I shoot rollerblading, so I have a pretty good idea about what you're trying to do.

I'd say use your 540ez as the on camera flash, then get vivitar 285hv or vivitar 283 (both can be bought for under 80 bucks each), and a decent wein optical slave, there is one on BH that is made for the vivi's.

If you use it indoor, it will give you a great range of use..but outdoor in sunlight, any optical slave will be sketchy at certain distances.

I don't believe there is actually a working optical slave and flash that will trigger the 540ez, but then again, i'm probably thinking of the 550ex.

I can tell you that for skating shots....a vivitar is a great slave, and two of them work even better.

Hope that helped, butit probably didn't :-/

Jeff, you're running into a very common problem with Canon Speedlites. Some of them work fine with generic optical slaves and others do not. They usually just fire once and then lock up. You can unlock them by turning them off or pressing the "open flash" button, but as soon as the optical slave trips them again, they lock up once more. Like I say, some people have no probolem with their Speedlites but your experience is more common.

Also, the model does't matter. i have owned 540EZs that worked and others that didn't. Same with 420EZ, 430EZ and 550EX. Some work with slaves & some don't. And I tried lots of different slaves with no change in results.

With some Speedlites you can isolate the four unused pins on the flash foot (use tape) and this will get them to work, but that wasn't successful with the Speedlites that I tried it on.

What I finally did was get a Ikelite Lite-Link for this. It's a TTL slave but it works very well with the flash on manual too. It's also very sensitive & works well outdoors. It's $80 at adorama.com

hey everyone,

thanks for the answers, i put my wein on my canon, and it fires just fine, i can make it fire over and over again, and no lock up, so mine must be a lucky one...haha. anyway, my question is this, it's kind of about guide numbers and such.

alright lets say im using the 540ez in manual, because its on a slave.. i place it like 10 feet away from my subject, however it is also like 10 feet away from me on the left or right hand side, my focal length is like 50mm..now how would i know what to set the power at and the zoom on the 540 ez? i checked in the back of the manual and it has the guide numbers, when i look under the column for 50mm zoom length, it says for about 12ft set the manual firing flash power at like 1/128. SO the 540ez would be my main flash and i would have a fill on my camera, that was not set very powerful, more or less jsut enough power to set off the slave. Do i have this correct???or do the guide numbers and focal lengths in the manual only work like this if the flash is on the camera???

thank you so much, i've just been reading as much as a i can, and want some sense of what im doing before i try this out, oyah im using a canon eos a2, with a 28-70mm lens.

any guidance on guide numbers and setting up multiple slaves and whatnot would be greatly appreciated!

The guide number changes with film speed and the flash head's zoom position. For example if the zoom is at the 24mm setting it's 28, at the 50mm position it is 42 and at 105mm it's 54 (all in meters at 100 ISO). But they remain the same if the flash is at the camera position or if it's off to the side.

If your subject is 12 feet from your flash, and you are using 100 ISO film, you would need to set your lens aperture for about f/11. At 1/4 power, you could use f/5.6, at 1/16 power you could use f/2.8. At 1/128 power you would need a lens aperture of f/1. I don't think you have one of those. :)

Of course, you could use faster film. 800 ISO film should allow you to us f/2.8 with 1/128 power at 12 feet.

This is all assuming that Canon's guide number can be relied upon. I find them somewhat inflated in most invironments. So with print film, I'd set the aperture one stop larger (smaller number). For slide film I'd use a flash meter or bracket the exposure.