Speedlight/stobe combination question

[tim]

I have two studio strobes (optical slave) and two speedlites, and I want to use them together. If I put the 580EX on the camera, on manual/master, and the 550EX slaved somewhere else in the room, will there still be a preflash that would trigger the studio strobes?

[SkipD]

I can't answer the question about the pre-flash, but there's something you need to consider. If you are using the Canon flash units in anything but full manual mode, the camera/flash units aren't going to know anything about the studio flash units. If the studio flash units trigger properly, you can expect overexposure at the very least.

To test whether the studio flash units are triggering properly, try this simple test. Put one of the studio flash units INTO your picture, aimed so the camera can see the flash itself. Take the picture. If the studio flash is bright in the picture, your triggering is OK. If the studio flash is dark in the picture, it got triggered with the pre-flash.

Once you get the triggering right, use everything in full manual mode. Measure the light level from the entire flash system with a good meter. Set the camera (also in manual mode) aperture for the level of the flash light. Set the camera shutter speed for any natural light that you want included in the shot.

[scottbergerphoto]

Tim, there are three ways to go in that set up. The 580EX in Manual/Master is going to set off a series of pulses prior to the flash to control the other speedight. You can't do it without optional equipment or losing one speedlight.
You can:
1.Set one speedlight on camera to Manual mode (not master). Set the strobes to slave. Leave the other speedlight in your bag.
2.Put a PW transmitter on the camera, a reciever on both speedlights in Manual Mode witha PW cord (hot shoe to miniphone), strobes on slave.
3. On camera flash on Manual/Master, off camera speedlight on slave, a digital slave attached to each strobe to ignore the preflash(pulsed instructions).
The problem/complexity arises from the Canon speedlights not being able to function as simple optical slaves.

[tim]

Skip, yeah I was talking about full manual, and I can use my meter (Sekonic 358) to work out my aperture, and good thinking on the test. I just thought someone could tell me about preflashes on manual mode without me doing the test.

Scott, thanks, I thought that might be the case. My main aim was to have a hairlight, which I guess I could use one strobe for while I use the 580 on manual. Canon's flash system is mostly good, except when you want to do things they assume you don't need to do.

I wonder if the cheap vivitar flashes are optical slaves... I know the Sigma 500's can do that.

If I get strobes myself (judging by my record, that should say when, not if), i'll get a couple of AB800s and a 400 as backlight, and I won't have to worry about pulling together things like this.

I still have something not quite right with my eyes from the other day, i'll go see an eye doc monday morning, and i've cancelled my shoot this weekend. It's probably all fine, but no point risking my eyesight eh?

[SkipD]

I'm wondering if a Canon EX flash could be triggered (in manual mode, of course) with a slave like this: http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=163363&is=REG&addedTroughType=search

The idea I have is to trigger one studio flash with a cable and let this slave trigger the EX flash as a hairlight or whatever. If you short the center pin on the flash to the hotshoe frame (actually the spring-loaded contacts that touch the frame) on my 420EX, the flash goes off. If that's what the slave accessory would do, I would think this could be a solution.

[tim]

That would be ideal, but a note at the bottom of the description says "NOT compatible with Canon flash units." :( Thanks for the link though :)

[scottbergerphoto]

When you try to use an optical slave with a 550EX in manual mode it fires once. Then you have to turn the flash off and back on to recycle it each time.

[robertwgross]

If you try to mix Speedlites and studio strobes, aren't you going to get two different color temperatures of the light?

---Bob Gross---

[scottbergerphoto]

If you try to mix Speedlites and studio strobes, aren't you going to get two different color temperatures of the light?

---Bob Gross---
Yup. Custom WB time. You can also shoot the first shot of each series with a white card, grey card, or white/black/grey card and in ACR click on that for WB and apply that WB to all the shots in the same series, unless you change the lighting.

[tim]

Good point, maybe i'll just use studio lights and reflectors when I do this shoot. My other idea was to use constant halogen lights as a hairlight, but that'd be even worse.

[scottbergerphoto]

My other idea was to use constant halogen lights as a hairlight, but that'd be even worse.
Don't forget the sunscreen. :D