An Underwater Photographer’s Guide to Colour Photography

Have you ever wondered why it might be important for underwater photographers to understand colour in photography?

It’s important for anyone with a camera, but most especially for those of us who create our images beneath the waves.

Read more: An Introduction to the Power of Colour Photography

What happens to colours in underwater photography

As we dive underwater, natural light from the surface is absorbed. Natural light is made up of many different wavelengths of light, and as these coloured wavelengths are absorbed, they disappear. This affects the colours we can see below the surface.

The ocean itself appears blue from the surface, but this blue colour is caused by the water absorbing all of the reds, oranges, and yellows (long wavelengths) in the light spectrum, leaving only the blue parts (short wavelengths) of the spectrum for us to see.

In the UK, the sea can have a slightly greener colour. This happens as light bounces off sediment and floating particles in the water, causing a more turquoise tone.

In the tropics, for example in the Red Sea, the sea is more often a very bright blue colour. This is because the water is clearer and contains fewer particles and sediment.

So now that we know that different colours of light have different wavelengths and that these colours are all absorbed at slightly different depths, we understand that we can see some colours deeper than others.

As we sink underwater, the first colours we lose are the reds and oranges, as their long wavelengths are the most quickly absorbed by the water in the first few meters. The next colour to go is yellow, then green, and finally blue.

This loss of colour at depth affects our underwater images, often resulting in dull images that lack saturation, vibrance, and contrast. But don’t worry! There are many options to revive the colours in your underwater images, both ‘in camera‘ and in post-production.

In this article, we’ll look at some of the best ways to make sure the colours in your underwater images are true to life.

But why is colour so important to underwater photographers?

When exploring the underwater world, we can see how beautiful and colorful the life is with just our eyes; if you use a torch, you will find everything appears a little more vibrant than it looked without the added light.

If you don’t use any lights, flashes, or filters when taking underwater photos, they often appear dull and green, lacking those wonderful colours that you saw.

Read more: 8 Essential Skills and Techniques for Underwater Photographers

White balance in underwater photography

There are a few things we can do to revive our images and fill them full of colour once again. The simplest change is making use of a handy tool called white balance (WB).

Your camera can be set to automatic white balance, or you can set it manually. It’s quite simple to adjust the white balance manually; simply dive underwater and take an image of a white slate or maybe a buddy’s white fin at the start of your dive!

This helps your camera to adjust the colours. It will know how much colour has been lost and will automatically add some of those reds and oranges back into your photos.

Just be mindful that you will have to readjust your white balance every time you change depth if you choose to manually set the WB.

You can also adjust the white balance in post-production software. In Photoshop and Lightroom, it is very simple to adjust the white balance and overall colour of your image to recreate the scene you remember from your dive.

Read more: What is White Balance?

Filters

Filters are another great way to make your images a little more vibrant, without the need for an external light source. There are quite a few types of colour filters for cameras out there, but only a few are useful when colour correcting.

As we dive deeper, we lose reds and oranges, so adding a red filter to our cameras will help rejuvenate the colours in our images and bring back the warmer tones that we are missing out on.

Generally, filters are best used when you’re deeper than five meters, as when you’re in the shallows or snorkelling, there should be enough light from the surface.

However, light red or orange filters are available if you are still struggling to bring back the rich colours from the shallows. When diving at depths greater than five meters, a red filter will work well until the scene becomes too dark entirely.

There are quite a few brands of filters along with lots of cheaper options on sites like Amazon; some of the best filters are by MagicFilters, Backscatter, and Keldan – they make a range of coloured filters to fit specific cameras alongside threaded filters.

Top Tip: These rules are slightly different for freshwater or green-tinged water, where a magenta filter will be a much better option to keep the water looking a little less green!

Other useful filters to consider are the Magic filters; I have used the original magic filter and the green-water version, and both perform very well and leave you with more vibrant underwater images.

My best advice when using filters of any kind is to be aware that any white light, such as surface light or torches, will also become the same colour as your filter.

So any dive buddies that you photograph with torches will look a little more like they’re holding a coloured lightsaber than a white torch!

Strobes and video lights

The depths of the sea are not only lacking in colour but also in light in general. If you have the budget available, using either strobes or video lights is the best way to reintroduce colours absorbed by water.

Both types of underwater lights use artificial white light, allowing us to see all the colours on the reefs and adjust the light output to suit the environment.

The light output only adjusts the brightness of the light and the distance it travels. So, if you just want to light your subject and leave the background to be darker and duller, then a low-power light is best, or even a snoot.

And if you are using a wide lens and want to illuminate a large area, then high-powered lights and perhaps even two of them are the best option.

Another thing to consider is the color temperature of your artificial light; if it is too warm or too cool, then you can buy corrective filters to add to them and adjust the temperature to suit you.

Read more: How to Choose a Strobe for Underwater Photography

The colour of the water

Now, as you have probably noticed when looking at underwater images from around the world, the colour of the water can vary greatly depending on the location and the weather conditions.

Here in the UK, our temperate waters are classified as green water, so magenta filters or strobes/lights are required on the majority of our dives.

Our waters can vary from a deep green colour during spring algae blooms to a nice clear turquoise colour in the summer and a deeper blue in the winter as we have less particulate in the water.

Freshwater environments will have a green water or even a brown water colour; the same theory applies as in the sea. The more particles and sediment in the water, the darker and more murky the water will appear.

In freshwater, such as the cenotes, it is not unusual to see a brown/red water colour due to the type of sediment in the water.

Filters generally aren’t required in freshwater unless you’re diving deeper than 5m, where a green-water filter or even no filter at all and a white balance correction in post-production may be a better option.

Finding true blue

Tropical seas and reefs are where you are most likely to find the “true blue” underwater images. In your underwater images, it is important to balance the colour of the subject and the background to keep them both looking natural.

Many people favour this deep blue background colour in their images to add impact to a scene.

Exposure is important for a rich blue background; the best conditions are on calm days when the water is clear and when the sun is high in the sky and not covered by clouds; the blue will be brighter at the surface and darker at depth.

Shooting towards the sun can give your background a gradient, with sunrays and a bright area around the sun gradually darkening as you get closer to the seabed.

Shooting with the sun will give you a more even shade of blue across your whole background, and you can use some of the natural light to illuminate your scene.

I prefer shooting into the sun as I believe it creates more atmosphere, but it’s a personal preference, and it is worth experimenting with both styles.

Something else to consider is the settings you are using to achieve the background color, particularly the shutter speed. It is important to make sure you are properly exposing your subject and not over or under-exposing the background either.

Take some time to adjust your settings and do a couple of test shots before approaching any skittish subjects.

The shutter speed will affect how bright the blue in the background is:

• If you’re trying to achieve a black background, you will need a high shutter speed of around 1/1000th and a low ISO (something like 200 or lower if you can).
• As you change your shutter speed and lower the speed, the light slowly returns in the background lightening the blue color. At around 1/250th, you will have a dark blue background slowly becoming lighter.
• When you get to 1/80th, you should have a nice royal blue color. This is a little dependent on your camera system and other settings, but as you slow the shutter speed, it allows more light to enter the sensor and brightens the background.

There is no right or wrong when creating a shade of blue in your images, and ultimately it’s our own creativity that determines the final colour.

Some photographers like Alex Mustard have a signature shade of blue “Mustard Blue,” and you can instantly recognize this, while others let the scene and sunlight do the work and replicate the colour they remember from the dive.

It can be fun to experiment and try to copy the shades of blue in other photographers’ images; this is not only a challenge to work out what settings they may have used but worth taking the time to practice and understand how they achieved success.

You can then work out the formula for our own signature shade of blue!

Post-production

Generally, as with all photography, the aim is to get your camera colouration as true to real life as possible by adjusting your camera settings and white balancing.

It can be corrected afterwards, but be mindful that too much post-production editing can affect image quality. It is best to try and get it as accurate as possible in the camera.

Everyone develops their own post-production workflow, but I find the most common adjustments I need to make in post-production are in the various slider adjustments, and in shifting the white balance by using the eyedropper tool and selecting a neutral grey area, then allowing the software to do the correction.

If this doesn’t represent what you saw, then you may have to use the colour sliders to adjust the overall image colour.

If your image is too blue, for example, then an adjustment of the temperature (blue/yellow) slider can be used to bring some warmer tones back into your image.

If you then have a ‘too-green’ image, the tint (green/pink) slider can be used to renew some of the pinks you may have lost and help the water look bluer.

Top Tip: Images can sometimes seem a bit dull when uploaded to your computer or tablet, so if you need to make those colours a bit punchier, an increase in vibrance or saturation should do this, but try not to go over the top and make it unrealistic.

Be aware when editing your original image and flick often between the two; this helps me to check I haven’t gone over the top with my edit and the colours are still true to life.

Read more: 4 Ways to Fix and Edit Underwater Photos

In conclusion

Once we understand how color is affected below the sea, we can find solutions to accurately portray the wonderful colors of marine life with our camera.

Filters will help to correct colors without using lights or strobes and will help to keep overall equipment costs down for those on a budget.

Introducing light via strobes and lights will give us the most accurate colours but is also the most expensive solution. Once you have your images, you can use a variety of post-production software to edit and restore the colour in our underwater photos.

All in all, there are many ways we can adjust and enhance the colour in our underwater images!