How to get perfect colors for underwater video

Whether you’re a beginner or experienced underwater video shooter, getting good color from your camera setup can be a real challenge. Shooting underwater video can be difficult and with ever changing lighting conditions and visibility, you need to constantly adapt to the environment to achieve the best possible results. In this article, we explore the pros and cons of various methods used to achieve great underwater color and which of them might be best for your camera setup and shooting style.

The Basics

Before we get into the various methods of underwater color correction, lets learn some of the basics. Cameras measure color temperature using the Kelvin Temperature scale, which enables most cameras the ability to shoot accurately in various lighting conditions. On land, you might be shooting under tungsten light, daylight or clouds, and all come with fairly accurate presets. You might have seen them scrolling through your camera menus. And, while these presets are hugely helpful, most cameras today (including most phones) are set to auto white balance, meaning that the camera measures the light temperature and auto corrects for various lighting conditions. Most modern cameras do this fairly well.

But when we get to shooting underwater video, the auto white balance feature tends to fail us. It was simply never designed to accurately measure underwater lighting conditions. So, typically, cameras left on auto settings will have a very strong blue or green tint, creating a somewhat lacking image compared to what we can see with our eyes.

However, some cameras have white balance presets for underwater. These are quite helpful as they tend to look much better than the auto white balance feature, but they can never be completely accurate at various depths. The reason for that has to do with the way light reacts when hitting water.

Light & Water

When sunlight hits the surface of water we can measure it in various wavelengths. Simply put, we can break them down into red, orange, yellow, green and blue. When the light hits the surface of the water it diffracts and causes the various wavelengths to loose their intensity the deeper you go.

The first wavelength or color that we loose is the color red. Red is only able to penetrate about 10 meters deep, and that’s under fairly perfect lighting conditions with good water visibility.

Orange is able to penetrate 20 meters,yellow; 35 meters, green; 45 meters, and blue is able to penetrate much deeper. This is why footage captured at great depth tends to look mostly just blue.

If you’re a diver you might have noticed these color changes yourself. Everything tends to look more colorful at shallow depths and less and less so the deeper you go.

Also, don’t forget that color gets washed out from a distance as well, be that horizontally or vertically.

So, if the reef looks colorless from 10 meters away, get closer! Your shot will instantly improve.

I mentioned that underwater white balance presets can’t be fully accurate, and here’s why. First, the available mix of wavelengths/colors at any given depth is not a constant. It changes with light intensity and visibility. And, second, you can’t accurately rely on one single white balance setting for various depths.

Manual White Balance

The magic fix to underwater color is a camera feature called “manual white balance.” It exists on most cameras from compacts to mirrorless & DSLR’s, but rarely on action cameras.

Manual white balance is simply showing the camera a neutral color like white or gray and setting its kelvin temperature based on the neutral color.

The result is an accurate white balance reading for your current depth. If you go shallower, you’ll notice that colors are becoming too vibrant and that red and orange color might even show up in the highlights of the ambient sunlight.

If you go deeper the opposite occurs, where red, orange and yellow starts to fade away to the more persistent green and blue. To combat this you need to do another manual white balance reading at your current depth.

The most accurate way of doing a manual white balance is to either make use of your natural surroundings or to bring along an item of the correct color.

By natural surroundings I mean objects like sand, rocks or even white corals. Or you can bring items like a white or grey slate or get yourself a white pair of fins.

Regardless of your choice, a few things are important to remember. You need to make sure that the ambient sunlight is actually reflecting off the object you are white balancing off. If you are blocking the light, the reading won’t be accurate.

The best way is actually to have the sun be in front of you, that way the reflecting light won’t be blocked. Another important thing to remember is to make sure your cameras exposure is correct before taking a white balance reading. Regardless if you are using manual or automatic exposure, make sure the camera is not overexposing the bright area you are white balancing off.

No matter which method you use, once you’ve done your correction you want to turn the camera away from the sun and look through the viewfinder or take a test shot. This is because the colors of the ocean looks more accurate with the sun behind you, essentially illuminating everything in front of you.

If the colors look off, go ahead and try again. You can be doing everything right and still get varied results, so on occasion you need to try white balancing more than once.

With practice, you should be able to get more accurate and have better results using this feature. Once you have make sure you start using some of the other features that can improve your results even more!

Pro Features

Some cameras allow for storing multiple manual white balance values, meaning that you can switch between various stored readings at any given time. This can be helpful in some ways; for example, if a subject appears overhead.

By pointing your camera towards the surface you are now filming shallower wavelengths of color, hence your current manual balance reading won’t be accurate any more. The result of using said reading might be an excess of red or orange colors in the highlights of the sunlight, which can be hard to remove in post.

Instead, try switching over to a shallower reading (if your camera has this feature) and you will get a far more accurate image. If your camera lacks this feature, you can also experiment with the daylight preset or a custom kelvin temperature, which will essentially turn most of the image quite blue.

Once your white balance have been achieved, there’s actually another few tweaks you can do to it in camera under the ‘adjust’ feature. Here you can control the tint of the image, and I personally find this feature to be important and help turn an already good looking image into a great one.

Experimentation here is key as each camera manufacturer will use different color science, hence the tint will need to be adjusted according to camera type. Just remember that you ideally want the final image to look similar to what you can see with your eyes.

Red Filters

Another great helper in achieving correct underwater colors is red filters. Calling them red filters isn’t entirely accurate, as they actually come in a variety of different colors and strengths and probably deserve a separate article of their own.

However, the way they improve your image is similar and so we will cover their effect and the reasons why you might want one.

Red filters are more or less what they sound like: a colored filter attached either to your camera or underwater housing that helps your camera achieve accurate colors.

This is a tool that is designed for two separate uses: either to be used with cameras that can do a manual white balance reading, or cameras that can’t.

For the latter, the effect and intensity of the filter is often stronger as it is designed to work with a cameras automatic white balance presets. It’s also very simple to use. Just put the filter on and head out.

With filters designed for manual white balance in mind it’s also quite simple to use. You simply apply the above mentioned manual white balance effect while having the red filter attached to your camera system.

Regardless of your camera and red filter, the end result is often an image more accurate in colors, as the reds, oranges and yellows gets a boost and some of the green colors washes away.

I say, “often,” however, because in truth some red filters are not of high quality and can almost do more harm than good.

Worst case: they can have a negative effect on the overall quality of your image and cause an excess of colors applied, similar to the example above of heading shallow after a manual white balance. As such it’s recommended to invest in a high quality filter, of which there are many.

Underwater Video Lights

Underwater video lights have long been the best way of achieving a pleasant looking result in underwater images. Ever since the days of Cousteau, videographers have used them to brighten up dark oceans, bring light to caves and wrecks and bring out the full color of reefs and marine life.

And video lights have come a long way, both in quality, brightness and price. These days you can get lights for all kinds of underwater videography, from purpose built macro snoot lights to custom built wide-angle lights and everything in between.

But underwater video lights come with their own pros and cons. While the illuminated part of an image looks colorful and vibrant, the unlit areas often looks dark, lacking in color or detail. And while that can be an excellent way of creating subject separation it can also be the cause of an image not reaching it’s full potential.

So, what are the options? Granted that there isn’t enough ambient light in places like caves and dark seas, adding artificial light is sometimes essential!

Read more about Video Light’s Here.

Why choose when you can have it all!

In comes ambient light filters for underwater video lights. These blue filters do something very clever: they convert the light output into a color similar to the ambient light from the sun. Instead of having video lights “take over” an image with their different light output they are now simply adding to your color corrected image. In other words, you can put on your red filter, do a manual white balance read and finally turn on your lights, for a illuminated trifecta with amazing results.

This quite new combination of products have truly changed the look of images in the past few years. It too has its challenges, like how the ambient filters cut a lot of power from the lights, potentially leading to a reduction in output by almost 50%.

It is, however, a product well worth paying attention to in the future as it will only improve and get better.

Summary

Getting great color in your underwater images should be one of your top priorities, whether you’re a beginner or seasoned professional. It helps you stand out and learning how to do so will forever change your images going forward.

And, as we’ve covered in this article, doing so is mostly technical and requires understanding more than skill, meaning that most anyone can figure it out, regardless of experience level. For most underwater shooters it’s one of those “Eureka!” moments, and for many the immediate response will be “why didn’t I learn this sooner.”

So get out there and embrace the techniques discussed in this article, apply the right one for your current underwater camera setup and have your images improve instantly. Happy diving!