Sunpak makes a grip with a slave sensor that can work with your camera. You mount whatever flash makes you happy on the grip, although it is really best with something like a Vivitar or Sunpak auto-thyristor unit. There is no TTL flash control with these units, of course..

I'm not familiar with your particular camera, so I don't know if you can set the flash so that it only fires one burst. Most of the new cameras use multiple bursts, for both metering and red-eye reduction. The Sunpak grip has a slave sensor that understands these pre-flash bursts and will trigger the man flash at the appropriate time..

I believe Wein also makes an optical trigger that understands pre-flash systems..

If your camera has any sort of flash control, you may be able to dial down the flash to bare minimum, letting that trigger the main flash and not affecting the exposure so much..

Crime Scene PhotographyA small gallery of personal work: http://picasaweb.google.com/PID885..

Thanks for this info..

That sunpack grip for the price looks like a good thing although I see that there is a Digi-Slave Deluxe 3000 Flash that works as a slave for P&S and also as a hot shoe flash. A bit over $100 but looks like it is worth the chance pending my emailing them for some more complete specs..

Seems I have some options here. I still want to experiment with a length of fiber optic cable from the flash to the slave sensor if the slave sensors prove to be not so reliable..

By the way the Powershot A720 seems to use the auto focus light for red eye preconditioning, the flash fires once..

Thanks again!..

J45 wrote:.

By the way the Powershot A720 seems to use the auto focus light forred eye preconditioning, the flash fires once..

Red eye reduction and the flash pre-burst are two separate things. With digital, the flash fires a pre-burst for the flash metering then fires the real burst - these bursts may occur so close together that one can't see that there are two bursts happening..

From my research back when I was looking into doing something similar to what your asking, I found that the Canon A5xx and A6xx allowed one to not only switch the flash to manual (therefore no pre-flash), but could one adjust the power to low, medium, or high. Don't recall if the A720 has this option..

I eventually though decided on a Fuji F20 which unfortunately on the negative side doesn't allow one to dis-able the pre-flash. I knew about the Sunpack battery sensor grip and the Wein digital ready optical slaves, but never got around getting either one. I'd read negative comments of both and had doubts as to there consistency of operation..

Also I eventually figured that if I'm going to take an external flash, and various othere accessories (like a flash bracket) etc., then the size advantage (versus a DSLR) of a pocket-size P & S would be somewhat negated and so I might as well take my DSLR..

Anyway as it turned out though I was able to get a Sunpack flash I already had to work with the Fuji F20. The Sunpack flash I have is a Sunpack PZ 5000 AF which I bought off ebay for $50 and has a built-in (dumb - ie. non-digital) optical slave..

What happens is that the Sunpak, because it isn't digital ready will trigger on the pre-flash, recycle, then fire again with the main bust from the on-camera flash. As long as the Sunpack doesn't have to fire at full power then it can recycle fast enough..

That's basically I believe how any non-digital ready flash will behave..

If the A720 doesn't allow you aperture control then you need a flash that offers a variety of apertures for which it can work in auto..

The external flash must have it's own sensor (auto-thyristor) which it uses to tell it when to cut-off it's flash burst..

Meter the scene with you camera, take note of what aperture it has chosen then dial that same aperture in on the external flash. You can intentionally mis-match the camera and external flash apertures which then is a form of flash exposure compensation..

I placed a piece of aluminum foil over the F20 on-camera flash to direct/reflect it off to the side (towards the off-camera external flash held in my left hand) so that none of the flash from the on-camera flash illuminated the subject, but was only used to trigger (optically) the external flash which is itself angled to bounce off the ceiling/walls..

I knew about the un-exposed slide film trick, but had no slide film laying around and didn't feel like buying a roll just for this purpose..

Example pics.

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Good Day,Roonal.

'Money doesn't buy happiness, but it makes for an extravagant depression' by golf tournament sportscaster..

Great information and great pictures (and a great cat!).

The camera does have on and auto flash settings, at aperature preferred it has on or off. it is difficult to tell if the flash is double firing or not especially on the "on" setting of aperature preferred..

Also it does have various flash levels manually selectable..

Worth some experimentation..

I suppose that what ever flash device I choose, if it doesn't work it could be returned..

Your information is very helpful, thanks so much..

Happened to come across this today - if it works, then could use any hotshoe type external flash..

Sunpak Digital Slave Unit with Preflash Cancellation, Multi Flash & Sync Socket.

@ Adorama $40http://www.adorama.com/SUDSUWP.html?sid=1209957583441526.

Good Day,Roonal.

'Money doesn't buy happiness, but it makes for an extravagant depression' by golf tournament sportscaster..

Roonal,.

Thanks for spotting this!!!!.

Most interesting I found some fiber optic cable online from a surplus supplier that caters to the 'display' industry and there was one item and at about $2.50 a foot it is worth fooling with. fiber optic cable directly to the sensor would solve most problems anyway you and others have been extremely helpful here as usual!.

I think I will give this a try. I will look for a flash bracket for my 720 hopefully one that isnt too massive and does allow me to flip it for verticle camera holding shots..

I will post a question regarding flash units perhaps on the lighting section..

Thanks again, all, for your attention...