Off-camera flash

[koffiejunkie]

Hi guys,

I'm getting ready to shoot some portraits for friends of mine, which gave me the excuse to buy a flash head and a brolly. The only problem is, I can't get the damn flash to fire at full power. Here's what I've been trying:

Camera is in M, 1/128 (ideally, I'd like to increase that to 250), ISO 100, f/8. The camera's pop-up flash can easily handle this at the 1.5m focus distance.

Flash is in slave mode as described in the manual. Even pointing it directly at the subject, forget about bouncing it off the brolly, it's just not firing full power, and doesn't allow me to set it higher.

I got a PC sync cable and an adapter, thinking that with PC sync, the flash should fire full power, and I can adjust my exposure accordingly. But unfortunately the adapter I got was to put on a camera that doesn't have sync, instead of to connect a flash that doesn't have sync, and I couldn't find the correct one anywhere today.

To make sure my flash isn't just not powerful enough (unlikely, but just to be sure), I put it back on the camera, put the brolly stand in such a way that it's kinda half over the camera pointing forward, and aimed the flash as far into it as I could manage. Fired off a shot, and it came out fine.

The flash is a Sigma EF-530 DG Super.

Thanks

 

[BigAl-sa]

Off-camera cable? (Jessop's has a clone for half the price of B&H.) You then need to mod it to get the distance you need.

The ideal would be the Canon st-e2 transmitter, but that's very expensive and not sure whether it would work with the Sigma.

 

[koffiejunkie]

Yeah, the TTL cable would fix it for one flash, if I had another Sigma to slave to it. But my second flash is an old Vivitar with 160v trigger voltage - so I have to use an optical trigger with it. I figured out that flash power wasn't the problem. Because I was using the pop-up flash, the optical triggers picked up the pre-flash.

I have looked at Jessops' cable - it's about £30. Thing is, I suspect that will give me the same issue with pre-flash. I have another week, so I'll get the right sync adapter for the sigma. That should get rid of the pre-flash issue. I'll let you know how that works.

 

[bwana]

Koffie. How much did you pay for the umbrella? And by flash head do you mean a umbrella clamp or another strobe?

 

[chau]

Hey koffiejunkie, how often are you planning on using off camera flashes? I ordered a set of Cactus V4 wireless flash triggers from Gadget Infinity last month and I can fire my flashes wirelessly without any hassles. The transmitter and receiver cost US$39.95 and a second receiver cost $23.95. It's a cheaper alternative to the Pocket Wizzards and it works pretty well. They reckon that the receiver can handle a trigger voltage of up to 300 volts so your Vivitar wont fry it. The company is situated in China so shipping will take roughly 15 days and that will be too late for you, but if you are planning on using off camera flash more than just once you could consider it.

 

[koffiejunkie]

Koffie. How much did you pay for the umbrella?

£29 each.

And by flash head do you mean a umbrella clamp or another strobe?

I meant the flash/umbrella mount - this one.

Hey koffiejunkie, how often are you planning on using off camera flashes?

Depends on how well this shoot goes

I ordered a set of Cactus V4 wireless flash triggers from Gadget Infinity last month and I can fire my flashes wirelessly without any hassles. The transmitter and receiver cost US$39.95 and a second receiver cost $23.95. It's a cheaper alternative to the Pocket Wizzards and it works pretty well. They reckon that the receiver can handle a trigger voltage of up to 300 volts so your Vivitar wont fry it.

I have looked into this, and if I end up shooting more of this kind of stuff, I would seriously consider it. But for now I really just need a sync adapter for the flash. My camera has a sync terminal, I have the cord. I have the optical trigger for the Vivitar, so if I can get the Sigma firing without pre-flash (which I understand the sync cable would allow me to do), then I'm good.

 

[bwana]

I'm learning to make do with the built in remote that the speedlite and sigma share. One on and one off camera, at least until tomorrow when I get my hands on the 7D.

That said I'm not a big strobist. My studio is pretty well set up now for continious lighting.