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Natural Color for Your Underwater Videos
by Harry Averill:
Few things in diving have changed as much over the past 20 years as the equipment for underwater imaging. In the 1990s, a basic camera system for still photography would set you back at least US$1,500. The price tag for video would be even higher and, worse, the size and weight of such equipment made it something you couldn’t take with you on every dive.
Today, divers can choose from a wide assortment of compact, affordable underwater cameras for both still and video. In fact, most cameras do both.
The camera we see most frequently is the GoPro Hero series. Today, it is unusual to see a dive team enter the water without one of these compact, versatile units. And, in so far as the GoPro is primarily a video camera, we see an ever-increasing number of divers trying underwater video for the first time.
No doubt, many first-time videographers dream of how they will dazzle their friends and loved ones with brilliant, colorful underwater footage. Imagine their disappointment, then, when they discover that, unless they shoot in very clear, very shallow water, their footage comes out a flat, monochromatic blue or green.
It doesn’t have to. There is a wide assortment of accessories and techniques that can help any aspiring underwater videographer achieve more pleasing, natural color.
Striking a Balance
The starting point in achieving the most natural-looking color for underwater stills and video is white balance. Your camera’s white balance setting determines how it will interpret the colors it sees.
By default, most cameras assume you are shooting above water, in daylight. Under water, colors such as reds and oranges are absorbed almost immediately, leaving the camera struggling to make sense of a world in which the only apparent colors are blues and greens. The result is the flat, monochromatic look we see in all too many underwater videos.
Fortunately, most digital cameras allow you to adjust the white balance for better, more natural underwater color.
Dedicated underwater camera systems, such as those from SeaLife, come with one or more underwater white balance settings. These automatically compensate for much of the color loss under water and may be all you need to achieve pleasing color.
If your camera doesn’t have a specific underwater white balance setting, the setting for cloudy or overcast conditions may help improve matters. In many cases, you can scroll through the various white balance options until you find the one that works best for your current depth and conditions.
The Holy Grail of white balance is the ability to adjust this setting manually. To do so, you point the camera at a pure white surface, such as an underwater slate, then push a button. By doing so, you are telling the camera, “This is what white is supposed to look like under these conditions.” The camera will do the rest.
Unfortunately, the GoPro currently offers no options for setting white balance. This means that, if you are shooting one, you need to pursue other options.
Let There be Light
If you shoot close-up or macro subjects, in overhead environments or at night, one of the best ways to achieve natural-looking color is to use video lights. These are available from a wide assortment of manufacturers.
Underwater video lights used to be bulky and expensive, and required the use of large, separate battery packs. The advent of LED technology, coupled with lithium-ion batteries, has made these lights both compact and affordable. The trays on which you mount your camera and lights have the further benefit of adding much-needed stability to compact cameras like the GoPro.
The one thing you need to be aware of with video lights is that, when shooting in daylight, even the most powerful lights may only be good to a distance of a little less than 1.0 m/3.0 ft, depending on conditions. Past this, you will need to look for other solutions.
The World Through Rose Colored Glasses
Among the easiest and most affordable ways to achieve pleasing color with cameras like the GoPro is with filters. These are available from several companies, including well-known names such as Polar Pro and Backscatter.
An amber color filter will help you rid your footage of the “blues” normally associated with shooting in clear, salt water. A magenta filter will do a similar job in fresh or green water. The difference can be very dramatic.
The one thing to be aware of with filters is that, while their use can result in more pleasing colors, they won’t necessarily result in the most natural color. In particular, rocks and corals that appear to be a shade of gray to the naked eye can look muddy and brown when shot using a filter.
You Can Always Fix it in Post…
The technology available for video production has become so powerful, even the best producers assume that sloppy shooting can always be fixed in post-production. While you should always strive to achieve the best-looking color you can before you start editing, the fact is that color related problems which cannot be addressed through white balance, video lights or color filters may still be fixable in your video editing software.
One of the factors which has put video production within the grasp of the average diver has been the availability of inexpensive, easy-to-use editing software that can run on almost any desktop or laptop computer. While the most basic of these programs may lack much in the way of color grading ability, as you move up to higher-end programs, such as Adobe’s Premiere or Apple’s Final Cut Pro, the ability to fix otherwise hopeless footage may surprise you.
A good starting point is with contrast. Many cameras, such as the GoPro, tend to flatten the dynamic range of lights and darks, in an effort to better compress video file size. Unfortunately, the result can be dull, flat-looking video. Increasing the dynamic range can have a dramatic effect on video quality, even before you address the issue of color balance.
After having achieved the best balance of lights and darks, the next step is to balance the reds, blues and greens. Understand that you cannot do a lot to restore reds to footage shot at depth; attempting to do so artificially can result in ugly, unnatural results. What you can do, however, is achieve a better balance between blues and greens, while bringing out some of the reds, yellows and purples, if they exist.
A software fix should be your last resort, and is no substitute for having achieved the best possible color before you get to edit. However, if you can feed your computer well-balanced, natural-looking footage going in, what comes out the other end will look that much better.
This article is a starting point. Your next stop should be YouTube. Search for underwater color correction. You will find a host of tutorials covering what you can do with programs ranging from GoPro’s free editing software, all the way up to high-end programs such as Premiere and Final Cut Pro.