A shot in the dark in Weebubbie Cave

About the trip

I’m winding my way down through the Adelaide Hills this morning, after watching the sunrise peek through the clouds. After time spent in the desert the road signs seems like information overload and there’s a lot of people around. We spent the last week at Weebubbie Cave, just over the West Australian border. Weebubbie is beautiful, and not just because you have to appreciate something once you’ve put in so much hard work to get there. Weebubbie has massive tunnels lined with white limestone and full of crystal clear water. From my point of view it was basically a week long photo shoot and I certainly flattened a lot of batteries in the process. Lighting the huge space in an interesting way was challenging, and it took some experimentation to get the shots I’ve posted here.

About the photo technique

When I set off the on camera strobes in smallish tunnels there’s a bit of leeway in which way the off camera sensors are pointing. Once the tunnel gets beyond a certain point of size or the walls get dark enough, the light stops bouncing back. This means the on camera light needs to hit the off camera sensors dead on and the distances at which the triggers will work is reduced.

Last trip in Weebubbie I had a number of frustrating experiences where the composition I wanted meant I was too far away from my model to trigger the off camera strobes. Over the last few months I’ve followed up on various technological solutions, including trying to find triggers that work on a different part of the EM spectrum with better penetration through the water. It seems that there’s not much that’s going to get through the water distance required fast enough for the camera shutter and therefore light-based triggers may be the best solution.

So if the triggers weren’t going to work, I considered putting down additional strobes on the cave floor between myself and my model. The chain strobing effect would put out extra light but also seriously slow down the dive. Another difficulty is that the floor in Weebubbie is covered in incredibly fine white silt. Each strobe placed down was going to create a milky cloud in the water, mid-photo – not ideal.

In the end, the solution that produced the photos above was an old-fashioned one. Instead of trying to trigger off camera light with on camera strobes, this technique relies on human co-ordination and timing. I moved the camera into B for “bulb” mode, turned off one strobe and pointed the other one back behind me. When Stefan saw the backward pointing strobe go off as I opened the shutter, he would manually trigger the off camera strobes, and I would take my finger off the shutter. With shutter speeds around one second all of our dive lights had to be off. I took a very dim LED backup torch and hung it down out of my drysuit pocket, which gave just enough ambient light so we didn’t swim into the walls. It was too small to show up in the photo, and also not enough to really help with framing shots of my invisible model in an inky black cave.

Taking photos in bulb mode like this created both more freedom and more restrictions. I could be as far away from the subject as I wanted, but it was very hard to compose the shots accurately. I had only a minimal idea of where my buddy was in relation to my lens, and that could change by the time he flashed the strobes. No way to time photos to catch bubbles here. Removing the foreground lighting also changes the way the foreground rocks are shaped from the camera’s POV, and that took some trial and error to improve on.

About the dive

We had three different sessions in the water trying this technique, with a photo review and improvement discussion each night. In the end, the most important predictor for success was getting everyone in the right place and all communications completed before turning off the lights. Once my eyes adjusted to the tiny amount of available light and with lots of water to swim around in, I really loved taking these shots. Floating in space, disconnected from everything, feeling the cave more than seeing it…all great fun. I hope you like the results.