Colour is incredibly powerful in our pictures. It transforms atmosphere, grabs attention and communicates the splendour of the underwater world. Cool blues speak of the tranquillity of the deep, while warm primary colours push subjects forward, making them jump out of the frame. The work of the world’s best photographers is often distinguished by how they capture light and colour, combining the richest blue backgrounds and all the magnificence of vibrant life.

Colours become even more interesting when we consider how to combine them. A palette of similar hues is restful for our eyes and creates a feeling of peace, such as the blues and greens of a kelp forest or seagrass meadow. Opposite colours jar, increasing visual contrast and the impact of our images. Background water colours are typically blues and greens, so when we shoot foregrounds of the opposite, warm colours – reds, oranges, yellows, pinks and purples – they really stand out strikingly against them.

Think of how eye-catching an orange garibaldi looks framed in front of giant kelp or a yellow anemonefish and red skirted anemone balled up in the late afternoon against the deep blue waters around a coral reef. It is why one of the oldest pieces of advice in underwater photography is simply get a bit of red in the frame! The deeper message is that when we take control of the colours in our pictures, we can truly move to the next level.

Warm strobe light has rendered a rich blue colour behind these ghost pipefish Equipment & settings: Nikon D2X, 10.5mm lens (15mm equiv.), Subal housing, Subtronic strobes, f/10, 1/15s, ISO 100

Warm strobe light has rendered a rich blue colour behind these ghost pipefish.
Equipment & settings: Nikon D2X, 10.5mm lens (15mm equiv.), Subal housing, Subtronic strobes, f/10, 1/15s, ISO 100

Filters on your lens

Filters are not new to underwater photography, but in sharp contrast with land photography, their use has blossomed in the digital decade as an alternative to strobes for capturing colour in the big blue. Underwater filters, also called red filters (despite all the best ones not being red), are valued because underwater colour casts are far greater than on land.

White balancing alone will always give inferior results. This is because whatever magic the camera’s or computer’s software weaves, a physical filter ensures that the sensor captures a more evenly balanced picture to start with. Your starting point is much closer to your goal. The difference between using a filter and not using one is often most visible in the backgrounds, which are a much richer, more pleasing blue.

Creatively, filters are exciting because they add colour in a different way to strobes, with colour penetrating much more deeply into big scenes. They require suitable subject matter, in the right conditions. The best subjects are coral gardens, wrecks, big animals, schools of fish, divers in relatively shallow water – working best in the top 15 metres (50 feet). The best colours come through when we shoot with the sun behind us. Shooting against the sun and particularly up towards the surface mutes colour in silhouettes.

Coloured light

Many of us have our regular haunts, dive sites that we’ve visited and shot repeatedly. These are places where it is hard to get excited about subjects we’ve already shot. Experimenting with coloured light is a fun way to transform familiar scenery and critters. Strobes normally produce white light, but we can easily change it by adding a sheet of coloured transparent plastic.

Photographic lighting gels are not expensive, but coloured cellophane gift wrap also works perfectly. Double sheets over for a more intense colour. Orange, red and yellow colours will work best against blue underwater backgrounds.

Similar colours make images restful for our eyes. The blues and greens here work together to generate a peaceful atmospher. Equipment & settings: Nikon D2X, 12-24mm lens at 16mm (24mm equiv.), Subal housing, Sea & Sea YS-110 strobes, f/20, 1/15s, ISO 200

Similar colours make images restful for our eyes. The blues and greens here work together to generate a peaceful atmospher. Equipment & settings: Nikon D2X, 12-24mm lens at 16mm (24mm equiv.), Subal housing, Sea & Sea YS-110 strobes, f/20, 1/15s, ISO 200

Take control of your strobes

Powerful blue backgrounds are the essential canvas of stunning wide-angle photography. Conditions, the direction of light, and exposure are all critical, but the factor that is often ignored is strobes. It seems strange that our strobes can affect the water colour of our pictures, but it happens as a result of how digital images are processed. It is locked into our pictures whether you process them with software or take them straight from the camera.

Strobes produce white light, but some strobes produce bluer, cooler light, and some more orange, warmer light. This difference is small, but since blue is such an important colour in underwater photos the difference is very noticeable.

The effect is easiest to get your head around when we consider how the camera handles colours in a photo. When we shoot, the camera selects a white balance to reveal neutral, correct colours in the foreground. This is determined mainly by the colour of the strobe light. If the strobe produces cool light, then the camera compensates by slightly warming up the image. This is applied to the whole image: the foreground is now correct, but the background is also warmed up, and this makes blue water a more greeny, muddier blue. If we use warm strobes, the camera cools down the picture to correct the foreground colour and also adds blue to the background, giving a richer blue.

It is straightforward and cheap to use mild lighting gel filters to adjust the colour of your strobes. A few years ago I even persuaded Inon to make diffusers with this correction built in. So they are now available off the shelf. The effect of warming up your strobes is not huge, but taking control of it will pay you back in every image you take.

The final twist in the tale comes in green water. Here, of course, cooler strobes are preferable, because most photographers want to produce an emerald green water colour, rather than push it towards a greeny-blue.

This article featured in SD OCEAN PLANET (Issue 8/2015)