As soon as you want to photograph ordinary subjects, you will find that the amount of water between them and your lens gives you problems of image sharpness, suspended matter intruding, and the white light from your flash getting absorbed before it has travelled all the way through the water to your subject and back to your camera. So get rid of as much of the water as you can by getting nearer to your subject and retaining the image size by using a wide-angle lens. Wide-angle lenses are not used underwater to record the "big" scene so much as to allow the photographer to record an average-sized subject as clearly as possible.
Light is absorbed selectively by water. Not only does it get darker as you go deeper, but only the monochromatic blue rays of sunlight penetrate more than a few metres through the water. This means you need to bring your own source of white light with you, and, for still photography, that comes in the form of an underwater flashgun.
Corals by natural light (above)
and illuminated by flash (below).
Macro, or close-up, shots are the easiest form of photograph to take underwater. Cose-up kits allow you to enter the water with your equipment preset. Even your flashgun can be pre-positioned in relation to the framing device so that your results can be predetermined and always successful.
Placing the framer around the subject and releasing the shutter at the right moment is all that is necessary for a correctly exposed, well-lit, in-focus shot. Even those with more expensive cameras in submarine housings can pre-position their lighting. For this reason alone, many divers new to underwater photography start by concentrating on macro subjects.
A diver using a close-up outfit.
Have you noticed that many people use a camera as if it were a hunting rifle? They position their subjects under the central cross in the camera's viewfinder, then are surprisedto find that their photos come back with endless amounts of sky above the heads.
The same sort of thing happens with these photographers underwater. The camera's viewfinder should be used like a canvas of a painting. Fill the frame, compose your picture. Don't just "shoot to kill"!
Top: good composition.
Right: bad composition
... very bad composition.
Camera-shake is still the most common reason for failed photographs.
Because you are in a fluid environment you could be confused into thinking that everything is very smooth. The reality is that more often than not your subject is moving. You almost certainly are!
Modern-thinking photographers do not brace themselves by holding on to coral. It is important to use a fast shutter speed (one that represents only a tiny fraction of a second, such as 1/250), be as still as you can by controlling your breathing, and release the shutter as gently as possible.
This is easier said than done. Many cameras do not synchronise with their flashguns at such fast shutter settings. Then again, things often happen very quickly underwater, and some of the best shots have to be grabbed.
When you can, take your time. Move in a relaxed way and keep calm.
Right: colourful scene on a coral reef, taken with the breath held and a fast shutter speed.
Below: the same shot, with added camera shake.
Where best to place the flashgun? Remember, you are working in 'foggy' conditions. Car headlights on full-beam reflect off the fog and make it difficult to penetrate.
Fog-lights are positioned as far away from the driver's eye-line as possible, so do the same thing with your flashgun. Just as fog is caused by millions of tiny water droplets suspended in the air, the water you dive in has countless bits of detritus suspended in it.
By positioning the flashgun far from the camera's lens axis, you avoid reflecting the light off this suspended matter and deny your pictures the unattractive effect known as "back-scatter".
"Built-in" flashguns are good only for use in air. You should either position your flash at the end of a long mounting arm, or temporarily detach it and use it at arm's length. Be careful to hold it so that it does not intrude into your picture.
Modern camera electronics combined with through-the-lens exposure control, even for the flashgun, have made getting the exposure right almost child's play.
Upper right: Back-scatter in spades!
Lower right : A nice, clear picture of a shark,
with the flash placed to avoid back-scatter.
Your buddy might be called in to play as model, lighting rigger, or wild-life herdsperson. People who have buddies who intuitively do what they want are very lucky. Shots without people usually mean nothing to your non-diving audience.
Buddy exploitation. Imagine the scene without the diver.
Shots without people usually mean nothing to a non-diving audience.
Sadly, we usually have to work within the limits of the circumstances in which we find ourselves, but as far as possible you should restrict your work to dives when conditions are favourable.
Even Peter Scoones, that doyen of marine-life cameramen, once said to me that his ideal dive site would have gin-clear water, no currents, plenty of animal action, and be only a couple of metres from the surface. Dream on, Peter!
Modern single-lens-reflex cameras in submarine housings usually have automatic focusing. However, this is not usually responsive enough to cpture fast-moving subjects like mammals and sharks, and you can miss what's happening around you if your head is stuck to an eyepiece.
Pre-focus your SLR, or use a viewfinder camera and be ready to shoot from the hip.
There is enough to think about on a dive. Make all the technical decisions you can while on the surface and work to a predetermined formula that you know.
Upper right: What you're liable to get if you rely on your camera's automatic focusing; it just isn't fast enough to capture the subject.
Lower right: This is what you get when you pre-focus your camera in the expectation of meeting a fast-moving subject.
Diving can be expensive if you add up the cost of each minute under water, but the experience can be precious and is usually unrepeatable. Have lots of goes at a shot on which you are particularly keen. Be prepared to shoot lots of film. After all, it is probably the cheapest element of your underwater photography costs!
