Underwater Photography Tips & Techniques

Professional Photography Service | Tips & Techniques | Equipment

This is an extensive guide to tips and techniques for improving underwater photography. Here, in one place you’ll find all the known theory, extensive hands-on experience, examples, tips and technical solutions to making your underwater photography that much better. Taking photos under water is one of the most difficult branches of photography as the underwater world has such strange optical properties and is rather taxing on the photographer themselves. Very often for most photographers the only solution is learning by trial and error and mastering the world of underwater photography can end up being a prolonged and expensive learning curve. Here I aim to help you enhance your chances of success considerably, reduce that learning curve and see your photography diving result in better shots and more enjoyment.

Top Tip – Thinking about buying an underwater camera? Not all cameras can be used with filters. When choosing an underwater camera or housing consider spending a little extra and buying a model which allows you to change filters. Always buy the camera and the housing together as it can be difficult to find housings at a later date if a camera is no longer in production.

Colour Absorption

Colour absorption is a Major problem for many underwater photographers. As light penetrates water some of it is absorbed but it is not absorbed evenly across the colour spectrum. Longer wavelengths (reds) are absorbed faster than short wavelengths (blues). The absorption of red light begins within inches of the surface and is progressive to the point that by the time you reach 30 feet all red light has been absorbed. Although your brain has the ability to compensate for this, your camera cannot and photographs will be colour distorted, picking up only blues. Colour is not only absorbed as it travels vertically down through the water but also as it travels horizontally. Taking a picture of a subject six feet away at a depth of ten feet will have the equivalent colour loss as being sixteen feet deep, filtering out nearly all the warm colours and leaving the subject very blue This horizontal loss is why strobes are not effective over distance. To compensate for colour absorption you need to either shot in shallow water, use an artificial light source, use a colour filter and get as close to your subject as possible.

Shallow Water

Staying shallow allows for greater light penetration. In Tobago there are several reefs such as Kariwak, Dutchman’s, Black Jack Hole, Angel Reef, Top Rock and Cove Ledge where the reef crest can be dived at a shallow depth of 15 feet. This provides keen photographers with improved light penetration as well as extensive reef. Many divers make the mistake of assuming you need to go deep to find good stuff to photograph, but on these reef crests for example the corals are abundant and you have a good chance of finding a wide variety of marine life from macro to pelagic species. Improved light penetration will enhance your photography, if you are unable to use an artificial light source or filter then shallow water will improve your colour saturation to an extent. Shallow water may be combined with special filters to enhance colour balance.

Top Tip – When using auto focus for macro photography carry a small pocket light source. When natural light is reduced such as a lobster under a ledge or a shrimp inside a narrow sponge use the penlight to highlight the focal point and help the auto focus lock onto the subject.

Artificial Light Source

Professional photographers are very subtle with their use of artificial lighting. Light should be used to fill in the warm colours in an enhancing way without overpowering the subject or creating deep shadow. There are three main sources of artificial light, mounted movie lights, strobes and flash.

Whilst most modern digital cameras have a built in flash the only practical solution for underwater photography is the use of a strobe.

Strobes are used in two main ways. In wide angle shots a strobe is used for fill lighting or “balancing” and does not influence the exposure but simply “paints” in the colours. In close up or macro photography where there is little light to produce depth of field for the subject then a strobe is used as the primary light source. This is called “primary source lighting”.

Strobes however, suffer from the same problems of light absorption as natural light and are therefore not suited to distance. For a subject ten feet away the strobe light needs to travel ten feet to the subject and bounce back ten feet to the camera making the subject light travel a distance of twenty feet. No matter how powerful a strobe is, if you are farther than eight feet from your subject the photo will tend to be monochromatic. Beyond eight feet a strobe can serve to both fill in some shadow and also add slight definition to a subject making it a slightly different shade of blue to the background, but it will do little to bring out the warm colours. It is better therefore to get closer to the subject and reduce the distance the light needs to travel.

Positioning of a strobe will have a great effect on your photography. If your strobe is positioned too close to the lens you have an increased chance of backscatter. This is when suspended particles in the water reflect light from the strobe back toward the lens and appears as white snow in the photo. Reducing backscatter can be done by improving your buoyancy and thereby reducing the amount of suspended particles in the water, the less there is to create backscatter. However positioning the strobe correctly plays a major role in reduction of backscatter especially when suspended particles are not caused by the diver but by highly turbid water. Having a long extendable strobe mount arm will allow you to experiment and find the best position for your light source. In most part when using a single strobe you want to position it high over the subject, away from the lens but avoid creating an extreme angle. By doing this you can avoid lighting up most of the detrimental suspended particles. If you place a single strobe at too extreme an angle you will create harsh shadows, most noticeable when a single strobe is used as a primary light source for macro photography.

Top Tip – When using a new camera and light set up, predetermine three strobe positions. Make a note of them as A,B and C. Take the same photo three times with the strobes in the three different positions always in the same order, A first then B and lastly C. When you’re back on land you’ll see how each position has affected the photo and can begin to work from there.

Improvements in macro photography can be made by using two strobes. Correct positioning of two strobes greatly reduces harsh shadows and can eliminate backscatter. Two strobes also better reproduce the affect of natural light. Natural light on the surface comes from two sources, the sun and the sky. The sun produces bright highlights and the sky produces soft shadows. The use of two strobes will better reproduce natural light. By positioning them on either side of the subject at 45 degree angles, you will minimize harsh shadows. If you position one strobe slightly futher away than the other then you can re-create highlights on one side of the subject and soft shadows on the other.

Filters

The most commonly used tropical water filter is the CC30R, a magenta filter which re-distorts the light coming into the lens toward the red spectrum of colour. Filters do not add colour but selectively remove some of the overpowering colours. The CC30R removes some blue light but allows red light to pass through unhindered. By themselves filters will only help “restore” colour at shallow depths and at the deeper depths the filter may be of no use by itself. Modern filters are available for different environments, a filter designed for shallow water will not be effective at depth, and a filter for deep water will cause photos taken in less than 30 feet to become too red. Many filters are designed to be used with only available light so if using strobe you’ll need to select a filter made for use with artificial light. To combine a filter with a light source however you’ll need to use natural light as your primary and the artificial light for soft fill in. A colour balance test prior to diving would help you avoid disappointment. As filters selectively cut back some light you will also need to alter your exposure. Most filters come with the manufacturers “filter factor” number which tells you how much to increase your exposure. To get the most out of your photography it’s best to research the diving you will be doing at your destination and use the according filter. For example, it’s pointless buying a shallow water magenta filter for a trip to Saba where all the diving is deep, likewise, a deep water filter would not be much use if you plan making all your dives from shore in Bonaire.

When planning an underwater photography dive trip to Tobago, and choosing a filter to suit it is for the most part a magenta filter for blue tropical water that is advised. It’s also worth noting that the majority of dive sites are between 40 and 100 feet, and the most extensive reefs are around 50 feet. However it is also worth bringing (especially during wet season) a freshwater/algae filter such as the URPRO GR as we sometimes have a green hue caused by plankton blooms rendering the standard magenta filter for blue water ineffective.

Backscatter & Lighting

Every underwater photographer’s nightmare, backscatter is light reflecting of suspended particles and can ruin an otherwise great shot. The way light diffuses as it interacts with matter, depends on the size of the particles. For the ultra small water molecules, blue light is bounced off in all directions equally, while the rest of the light passes through normally. This diffusion explains why both the sky and the sea look blue. The diffused blue light appears to come from all directions, particularly deeper down and it has the effect of reducing contrast while dominating the natural colours.

Particles as large as phyto plankton but not visible to the naked eye act like mist particles, reflecting all colour components of the light back to where it came from. This form of diffraction causes images to.

Finally, the “snow” effect that plagues under water photographers and which is called backscatter, is light bounced off visible particles such as plankton organisms or disturbed sand. Such 'snow' or 'jelly' or 'snot' often collects close to the surface and should be avoided. Disturbed sand is generally localized and caused by the diver themselves, or other divers. To mimimise back scatter:

work deeper than 3m / 10 feet
shoot across the ambient light
avoid ocean swell that stirs up sand and dust
use long exposures (0.25-1 second). Particles that move will disappear from the image
use continuous movie lights rather than strobes
move cautiously, with good buoyancy and make no dust
move against the current: your dust drifts away behind you
dive alone: one diver creates less disturbance and has more patience.
use wide angle lenses, wider aperture and stay close to the subject

Strobelight scatter is caused by brightly lit small objects close to both the strobe light and the lens. As the particle is usually out of focus, it projects the scape of the aperture onto the film. It is a photographer's nightmare because it spoils the photo but more annoyingly because it is never visible when taking the photo. Fortunately a number of approaches can be followed to reduce its devastating effect:

Move the strobe backward. This can often easily be done using the standard strobe arm. Its effect is dramatic, especially for wide angle lenses. At the same time this results in more even lighting. For very wide angle lenses (fisheye, 13mm) the camera will soon be in the way of the light, resulting in an unwanted shadow of the photographer's head. For wide angle photography think of the strobe as your fill light, painting in the colours and not as primary.
Move the strobe further out. This requires an especially long arm or a buddy to hand hold. By enlarging the distance, the lighting is no longer frontal but strongly sideways. A larger distance changes the quality of the light and makes it more blue. Note that the further out your subject is and the larger, the further the strobe arm should be extended. It is not unusual to have a 1.5m strobe pole for lighting models and parts of shipwrecks!
Move the strobe away from the corners of the image, towards the centre of the long side. This effect is dramatic, but it also produces unnatural looking light. Also when turning the camera for a vertical shot, the side lighting becomes unnatural. But a compromise position can be chosen. Many photographers use the centre position for macro photography, as the light needs to be brought close in for subjects close to the lens.
By using a wider aperture, the intensity of the aperture projection becomes less and it may fade into the background intensity. But your depth of field also becomes less. The combined effect of a bright background and wide aperture removes most scatter. Practise shooting with a macro lens at f-4 and over one metre distant from the subject. You'll be surprised, especially in dark places!
Arrange a lighter background, particularly in the quarter of the image where the flashlight comes from. This can often be done. Even the sea can serve as such a background provided that ambient light is sufficiently allowed to expose the film.
Blinker the flash beam by placing a blinker or baffle between the flash and the lens. This method is cumbersome and doesn't work well so is a last resort.
Use more available light. By using the filtering techniques described above, the amount of flash light can be reduced by half, allowing for less strobe light and more ambient light. This is both easy to do and dramatic in result.
Use continuous light instead of strobe light and longer shutter speeds of between 0.1 and 1 seconds. The moving particles will then not be recorded. This method has given stunning results in estuaries with less than 1m visibility but it requires a steady tripod, still subjects, a movie light and takes experience.

Top Tip – Help eliminate backscatter and vastly improve your photography by first working on your buoyancy. Get correctly weighted so that you’re not too heavy and dragging fins or hoses or adversely too light and scrambling to stay in one place. Employ a frog kick to avoid stirring the bottom. Once you’ve got control over buoyancy you’ll then be able to learn breathing techniques which will help you with camera control, particularily if shooting on digital with a delay, breathing will also help you get closer to your subject.

Subject Angle & Approach

To get that really good shot of a marine animal you’ll need to position yourself and your camera in the right spot. The angle at which you compose your subject will greatly improve or spoil your photographs. Photographing a fish for example from above or behind will rarely produce a successful photograph. Imagine your photograph as being a conversation between the subject and the viewer. Just as you wouldn’t wish to talk to the top of somenes head or their back as they walk away, neither does this convey a good portrait of the subject. The best underwater photos of larger animals have an element of communication between the photographer and subject or interaction ( not physical but in the perceived sense of interaction )

Consider all the possibilities of the shot. If shooting on wide angle how can you add scale? Try to compose the photo to light up the foreground and get a sweeping background with a narrow depth of field? Would shooting upward into falling natural light and silhouetting the subject be more dramatic? Or how about that worms eye view from bottom level of a stingray? To get your subject composed in such a way that your photograph is appealing you’ll need to know a little about animal behaviour. Some animals such as garden eels will bury themselves when approached too rapidly so best approach slowly from the side. As they begin to dip halt your approach, as they get used to your presence move a little closer each time. Many marine animals are pressure sensitive and can feel you coming, move toward them slowly inch by inch and try to approach from down current, then when within your photo range remain still. Be patient as often after remaining still for several minutes animals such as featherworms, mantis shrimp or jawfish will re-appear. Re-breather technology is definitely the way to get closest to many animals but not practical for many divers, try exhaling slowly through the nose to muffle bubble noise and help get closer before they run and hide or bury themselves in their holes. Then there are psychological games you can play with curious creatures like angle fish, squid or sharks which will help bring them closer to you. But those secrets I’m not publishing on the web, you’ll have to dive with me to learn those.

Professional Photography Service | Tips & Techniques | Equipment