Blue water on Lonsdale Wall

About the site

Lonsdale and Nepean Walls border the deep water channel that runs into Port Phillip Bay. They can be dived at slack tide each day, when the water balances inside and outside the bay and the currents stop running. The flow of water means filter feeders like the bright yellow zooanthids, sponges and soft corals can be found up and down the walls.

Lonsdale Wall also runs a fair way into the bay and is protected in poor weather. As a result, it’s an easy dive to do when the swell is running and the wind is adding white caps on top. Which is convenient, but also means I’d dived the wall in terrible conditions and terrible vis more than once. And despite those green water dives with so much floating particulate that you need to hold hand with your buddy to keep track of them, I keep coming back. Just occasionally, we have one of those days where you remember why that is. These photos are evidence that when the wall is good, the diving is amazing.

About the dive

These photos were taken on Melbourne Cup Day, a public holiday Tuesday. Mum and I headed down the bay regrettably early for a holiday and got on the boat in flat calm seas. As we jumped in the water you could see the shot line arcing down into the blue as the last of the current died down.

The wall here dropped down into the blue with a couple of big stepped and undercut ledges. As we drifted gently along the steps turned into the big vertical drop you see here. With reef fish following, blue devils staring out from their holes and schools of hula fish we sailed along the wall. The combination of bright yellow zooanthids, coloured sponges and 20m vis through blue water made for a stunning dive.

About the photos

I’ve previously found zooanthids a tricky thing to take photos of, because if you don’t get enough light on them they come out a kind of sickly green colour. Balancing the fall off of the strobe light with the right shutter speed for the natural light can be difficult, but if you get it right the yellow against the water looks great. After a bit of experimenting I settled on 1/60th as the best shutter speed for getting the right blues and yellows at 25m depth.

The second challenge was finding some fish. The reef fish tend to scoot along the wall and while they’ll let you get relatively close, it’s hard to get them out against the blue water. In the first photo you can see Mum watching a well-disguised wrasse – obvious at the time, hard to see in the photo. For the second shot here I’ve rearranged my strobes to get right up close to the wall. From this angle the hula fish are out against the blue water, and while the magpie perch is resisting my efforts, at least his black and white stripes stand out.

All in all, I love almost every photo from this dive. Great vis shows off the beautiful colours of temperate diving. These shots sum up the reason I dive different bits of the wall over and over and over again….just sometimes, you get lucky.