About the cave
Tank Cave, Mt Gambier has kilometres of crystal clear, shallow tunnels perfect for testing things out. You can see the different areas in these two photos from the same dive – small twisting light-walled tunnels vs large dark chambers. All in the same still and clear water, so great fun for photography.
About the dive
Over the course of the weekend we dived down the gold lines and through J and K section, followed by a long swim to GS tunnel yesterday. All of the dives involved a trip out or a trip home under Lake Ayre, one of my favourite places to take photos. Taking photos under this huge reflective surface is tricky. The chamber is much larger than others in the cave, and relatively dark. The air/water interface overhead absorbs light rather than reflecting it back like white rock does. Getting divers and reflections lined up is tricky, and made trickier by the way the bubble of air isn’t quite central to the other lines of the room.
Overall, I usually leave Lake Ayre feeling that I haven’t quite got the shot that might be possible. I was pretty happy with my image of Ken entering under the Lake a few months back, which was differentiated by having a lot of off camera strobes on a single diver. I was still restricted however, by the camera to model distance. With the older triggerfish I was using at that point I needed to be within about 10m of my model to set off the off camera strobes. This challenge led to the move to bulb-and-manual-strobe-firing that I practised in Weebubbie, a technique that brings its own difficulties. Testing Hedwig’s new triggerfish over the weekend showed that even in large and dark-walled cave areas with very little light reflected, the off camera strobes would still go off reliably – miracle!
About the photo
The top photo here was taken on the way home. I swam out around the side of the lake, breathed all the way out, then crossed and swam back towards my buddies. This kept my bubbles out of the way and as a result the only ripples on the surface above are coming from the people in the shot. The still surface gives a great view of the roof above through Snell’s window. I’m not quite sure why I like this photo as there’s not a lot of contrast, and the composition is slightly off, and a few other niggles…but I do, and having sensors that work at 15m distance made it possible. You can see the new triggers in action in the second shot too, setting off both the strobe between the front diver’s tanks and the two behind her to create the halo of light. With more off-camera strobes, all things are possible.