Snorkelling: Why I love it as a photographer

David Doubilet summed it up nicely with the title of his beautiful book, Water, Light, Time. Three essentials of a rewarding dive experience. But this is not what dive operators want to give you, nor would most punters accept it.

Alone in four metres deep, with a camera, and without any thoughts in my head. The reverie is uninterrupted by concerns about air, safety, tomorrow, a buddy, nitrogen load, or even, these days, running out of film. You have a seamless proximity to the weightless delight of diving. Apart from mask snorkel and fins, a tee shirt, backpack, tank and reg is all the extra gear you need. No BC, no octopus, no wetsuit, not even a contents gauge. Bear in mind that pulmonary barotrauma is still a real danger on these dives, so as always, make sure you breathe out on ascent, even from a couple of metres.

I dived the Coral Sea many times. Always Spoilsport put us in great locations, steep edges, deep clear water with big animals. I love that too, but I always wanted to steam into the lagoon at Osprey and anchor on the sand - flat by the back - reef margin on the windward side. Here, I imagined limpid ocean water flooding over the reef top and back - reef margin, across a shallow sand - flat of perfect sand, dropping away into the more turbid lagoon. Oceanic reefs are like that. When the water is clear and there is sand below, the refracted shards of lucent turquoise through the surface can touch the soul.

With a slick of biological material coming off a reef to windward, the oily surface is tamed in such a way that the net of caustic light patterns scattering across the bottom are entrancing like an open fire. Endorphin, dopamine, serotonin; I don't know what it is but I'm addicted.

You can't expect a dive boat charging a lot of money to drop the divers in three metres of water. But we should ask, ‘Why not?’ On Spoilsport you can dive as long as you like, but most day boats would have a fit if everyone was in the water almost two hours, dithering around in the shallows. Their schedules would fall apart. Lunch would be a fiasco of absenteeism.

For a photographer, the shallows have so much to offer. Light, of course but reflections too. You will need all that light, because those dancing caustic light patterns will need at least 1/1000th to freeze them. With shallow water over a perfect reef in the calm, the upside down reef extends to infinity, drawing you to its horizon. Lie motionless on the bottom waiting for your bubbles to clear, so you can use the Snell's window for creative effect. On rougher days you can shoot fish against the underside of the rafts of foam coming off the reef, or jam your camera against the rock to capture swirls of bubbles at slow shutter speed. You can shoot sea birds or drifting rafts of pumice if there's a volcano handy. You can experiment endlessly, because you have time.

The meniscus; how I love the way it pastes itself across the dome in endlessly delicious curves. By angling the camera up, you can capture above and below and the reflection of the bottom in the underside of the surface. Angling down, I can see the image below and the subject refracted and disjointed through the surface.

It's not as though the shallows lack animals. I recall one dive outside the atoll of Takaroa, French Polynesia. There seemed to be no sharks at all, till I ascended and looked over the lip of the reef flat. There, greys were occupying the niche of black tip reef sharks in half a metre of water.

Outside the reef, on the leeward side, swells from a distant ocean will curl in glassy perfection onto the reef, held up by what little wind there is. I prefer to snorkel here, to catch the exquisite glass tubes as they curl above and disintegrate in a maelstrom of foam and vortices. In the surge you have the dubious delight of addled synchrony between your inner ear and vision. This is especially disconcerting over a kelp forest as it wafts back and forth. Surge is also the sculptor of those rippled dunes carved in the sand that look so wonderful in monochrome.

Late afternoon the sun strikes the surface at just the right angle to be refracted into a jangle of golden lances like crepuscular rays. A warm gel on the flash will add consistent lighting to your foreground subject, and a high shutter speed will increase the definition of the rays.

Even at night, a dive to two metres can be extraordinary. In Tonga I dived many times where basket stars unfurled shallow enough to touch the surface. Turn off the torch and in the moonlight watch the reef etched in bioluminescence, or swim with your eye to the viewfinder and watch as dinoflagellates slide across the dome in a cascade of stars from a distant vanishing point.

Some dive sites have both diving depths, 15-25m, and the shallows. Challenger Bay on the Great Barrier Reef is one of my favourites. It's so easy to do a normal dive there and miss the most beautiful areas. My maximum depth is seldom more than six metres.

What is so special about 15-25m? Deep enough to be called a dive, shallow enough to get an hour in the water, shallow enough to keep even the novices safe, but deep enough to get everyone out after an hour. Convenient for the dive operator at least.

Perhaps one day, superficial diving will become fashionable, like muck diving. But without the muck...