Off camera flash - part 2

I got hold of a hot shoe flash with the hot shoe attachment broken off. This didn't really matter as my point and shoot camera doesn't have a hot shoe fitting anyway.

Nevertheless, I was going to hook the two together so I could have off camera flash without the problems of working in the dark with slow shutter speeds as mentioned in part 1.

I found that the flash unit has two pins poking out the bottom, one sending a current (or voltage?) and the other waiting to receive it. By touching these two pins (or the adjoining wires) together I could fire the flash on demand. To link this up to my point and shoot I stuck an LDR across these wires and placed the LDR against the flash of the point and shoot camera. This means that the LDR is not letting (resisting) any electricity go round the loop of the two wires of the flash. Once the LDR gets enough light (in the form of a camera flash) it lowers it's resistance and lets the electricity flow through the loop, thus completing the circuit and firing the hot shoe flash.



Sticking this LDR on the end of some lengthy wires allowed me to get some distance between the flash and camera. The first problem I expected was that the flash might not trigger fast enough, but this appears not to be the case. Even in brighter situations where the point and shoot camera would choose a fast shutter speed the external flash still fires and is visible in the shot. In darker situations the camera needs to fire it's on body flash to focus in which case it is easiest to hold the LDR clear of the flash whilst focusing, then just press it against the flash to take the picture.
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Off camera flash

As previously mentioned; I hungrily consume every bit of information posted on the Strobist blog. As soon as I came across it I realised what it was about all the photographs that I love so much: off camera flash! Though a great deal of the information made little sense to me, the lighting ideas and techniques were thoroughly inspiring and I found myself wanting to explore all the creative possibilities of off camera flash.

I had one main problem: a point and shoot camera doesn't have a hot shoe fitting for an external flash (or wireless transmitter to said flash).

The first thing to come up with was some kind of flash creating device other than my camera, another camera. I could either ask someone else take a picture with a flash where ever I wanted the flash to come from at the exact moment I took a picture, or I could put my own camera into self timer mode and take the flash picture myself. Of course this is near impossible as a typical exposure (the time the camera is soaking up the scene) is around 1 60th of a second or faster (usually much faster), so very precise timing would be required. I got around this by using a longer exposure. My camera can fire at 5, 15, 30 or 60 second exposures. Fifteen seconds proved to be quite succesful.



The drawback to this method of long exposures is that you have to work in almost complete darkness, doing this with even just a bit of light would require shorter exposures and more accuracy. Using a long shutter is fun though, it lets you combine off camera flash with things like light-painting and ghosting, all in one shot.



With control of the aperture the level of apparent flash could be controlled which would help to avoid blown out faces and such. In this system it is only really practical to fire the flashing camera once (for crisp pictures) and something much more doable would be to have a reflective surface of some sort (paper would probably do) held up opposite the flash to mimic a lower power flash firing from the other direction.
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