UNDERWATER LIGHTING AND LEARNING FROM YOUR MISTAKES

In February I shot a night underwater scene of spear fishermen in Laos. There are two things that have stayed with me from this night’s filming - 1) the fishermen had been on the rice whiskey and found it hilarious to shoot their harpoons as near as they could to me while I garggled ‘noooooooooo’ through my snorkel. And 2) If there was any scene from this year I wish I could go back and shoot again it would be this one.

It’s not awful, it made the cut and it works OK but I have never been happy with it. The old excuses of limited time, difficult location and not enough planning time were all present that night but when it comes down to it my approach was wrong. I knew the theory but there wasn’t the thinking or setup time to execute it properly so I just went with the solve-all camera mounted lamps and I’ve regretted it ever since I viewed the rushes at 4am that night.

It’s now December and I’ve just shot the final episode of ‘Monsterfish series 3’ in New Zealand and the Solomon Islands. For the first time since that dry-season night in Laos we had a night underwater scene to shoot. I wasn’t going to mess it up this time.

Our location was the crystal clear Lake Rotoiti on New Zealand’s South Island - some of the clearest fresh water I’ve ever seen. The giant eels we were there to film live in the shade under a small jetty. They come out at night to feed.

This was a better location than Laos - easier to control, shallow water, above water access on the jetty, full scuba gear, the previous night shooting tests and eels that we found were not skittish in the slightest. I was determined to make up for the disappointment of Laos.

So here’s the theory - it’s pretty simple - the trick to lighting underwater is to not light the water between the camera and the subject. Underwater clarity is everything. If there are sediment particles suspended in the water (which there always will be, especially in fresh water) and you shine a light at them you’re going to see them, if you don’t they remain invisible and the camera effectively sees right through them. This is known as 'backscsatter'.

By blasting a camera mounted light forwards you only succeed in illuminating the sediment. Add to this the fact that light drops off faster in water than in air so the sediment near the camera/lamp burns bright while your subject a few feet away can be under exposed. Not a good look.

Here's a frame from the Laos shoot to illustrate the problem. The blacks have turned to haze with all the light on the particles in the water. It's as if the subject is behind a fog. Also notice the fast drop-off - the fish and face are correctly exposed yet his shoulder is burnt-out - less than a foot closer to the lamp.

There are a few ways to solve this problem. The most common is to angle camera-mounted lights in such away that they hit the subject but not the water directly in front of the lens. It's often the only practical way to illuminate underwater and yet for picture results it’s probably the worst - especially when it's done badly like in Laos. Above water I do anything I can not to use a camera-mounted light so I wanted to try to apply the same idea to underwater.

Given our ideal, controllable location wanted not to use camera-mounted lights at all. This is where the jetty comes in. We mounted a bright and hard L.E.D. torch on the jetty pointing down into the water. This created a shaft of light which the surface ripples refracted and broke up to make a beautiful shaft of ‘cathedral’ light underwater. With a little bit of creative license you could just about believe it was moon light shining down.

I then used a camera mounted underwater lamp dimmed to it’s minimum setting just to bring the tiniest bit of fill light into the eels in the foreground, without lighting too much of the sediment. I extend the lamp on arms forward and outwards from the camera so the lamp was almost a foot forward of the lens. This means the water directly in front of the lens is not illuminated, reducing the glare from the sediment. I also gave our host who was in the water with me a torch, dimmed to it's lowest setting as a practical lamp to use in shot.


The results were awesome. The sediment was not visible at all in some shots so the water just looks like a black hole with eels floating in and out of frame. On the jetty the team threw food into the shaft of light - the eels obliged and formed a feeding ball as if on a mark.

I did various shots but one of my favorites came from lying on the bottom and shooting upwards towards the light creating a silhouette of maybe fifty eels moving in and out of the light. Some eels would wander off to have a closer look at me and the camera light picked them out beautifully as they looked into the lens (the lamp dimmed so low that eels only 6 inches away from it were correctly exposed).

One side effect of this method is the water around myself was in complete blackness and from time to time five foot long eels would appear from nowhere and bump into my head. Quite a shock to start with but after a couple of hours down there we realised they really weren’t interested in eating us - not while there were people throwing sausages and tuna into the water from the pier anyway.

At one point I swam right through the feeding ball. One of the larger eels hit the catch that holds the monitor shut, flicked it open and flooded it! Oooops, well at least it wasn’t my fault for once. A few days drying on the heat of the dashboard and the monitor was back up and running.

I still wish I could go back and shoot the Laos scene again but at least I've now shot a night scene I'm happy with and proved to myself that I have learned something this year!