Lumina Ex Machina
This is slightly different in that to realise my vision here, I had to play around with backlighting, but on a circuit board this size – the front of a smaller graphics card – there’s no point just flicking a light at it from the back because you won’t get that your light in any specific area.
"A slightly more unusual project this time: some photography of an underlit circuit board…"
The solution in this case was to buy a Post Office box, cut a small hole in it, and then cover it with black card with a similar sized, matching hole.
The flash then goes in the box with a remote trigger set to manual mode, which is then sealed and made light-tight. The hole in the box was perhaps only 2 x 1 cm; basically, small enough to highlight the exact area on the board that you want without spreading light everywhere.
This means you just get a small square of intense flash that you strategically position your circuit board over. It still requires a lot of power off the flash; the circuit board is only slightly translucent. However, around the soldering points, you get a little halo of light. This was the effect I was after – the impression of the ‘fire’ of flowing electricity.
Lumina Ex Machina – the light from the machine.
To get the detail of the board, you just need your macro lens out; whilst I didn’t stabalise on a tripod, this might be necessary if you want a long shutter speed for more ambient, depending on the overall effect you want.
I didn’t do this here as I was relying on the light that did penetrate the board itself to give a little lighting, so I was working at the camera’s maximum sync speed (1/250 s, in my case). This can be seen from the board substrade, which is a little brighter than the circuit tracks themselves as these completely block the flash.
You can see the results of my experimentation in the mini-gallery below. Comments, as ever, are more than welcome.
All the best,
Chasing Rays Photography.