An In-Depth Guide to Shooting Sunbursts

An attractive sunburst lifts even the simplest wide-angle composition, Mexico
 

By Alex Mustard

I’m asked lots of questions about underwater photography, but one that comes up again and again is: “What settings do I need to capture the perfect sunburst?” It’s a question I’ll answer below, but the question itself actually reveals why people struggle: Some mythical camera setting is not the key to shooting sumptuous sunbursts underwater. The two most important factors are nothing to with settings: They are the correct conditions and the correct depth.

There are few subjects that we can include in our pictures that are as attractive and feel as characteristically underwater as a sunburst. Yet underwater photographers definitely have a love/hate relationship with the sun. Capture a sunburst correctly and even a decidedly average scene is transformed into a stunning photograph. But get it wrong and a badly shot sunburst will annihilate an otherwise beautiful frame. There is a good reason why underwater photographers nickname the sun as “the white ball of death”! With stakes so high, learning how to capture a sunburst in all its beauty is definitely worth your time. I’ve tried to pour as much knowledge as I can into this unashamedly meaty article. I’ve picked images from all around the world to show this advice holds wherever you dive.

Sea snake with midday sunburst showing radial light, Philippines
 

Coral reef with sun broken into layers of sunbeams by waves, known as dappled light, Egypt

Correct Conditions

Conditions are the most critical factor for capturing sunbursts and an experienced photographer can judge this from above the water, before the dive. Obviously, it is a prerequisite that the sun is shining, but just as important photographically is a reasonably smooth surface of the water. When it is windy, the surface of the sea becomes ruffled, which breaks up the sunburst, stopping the light from being focused into attractive sunrays. The sea doesn’t need to be mill-pond flat, but remember when you see sun and smooth water then you should be reaching for the wide angle and thinking about capturing beams.
 

The smooth sheltered water of a cenote focuses the sun into clearly defined shafts of light, Mexico
 

We can rely on luck to get such conditions, but it is better to seek them out. Many tropical dive destinations are exposed to easterly trade winds, so dive sites on the protected western sides of islands provide the smoothest water. Furthermore, as the land heats up more quickly than the sea each day, so a sea breeze develops in coastal areas with winds blowing from mid-morning to late afternoon. The calmest conditions are therefore usually at the ends of the day. Small-scale topography (like cliffs, small islands), corals or giant kelp growing right to the surface, or any obstacle to the wind (such as a dive boat) will also give us small pockets of smooth water, creating pleasing beams of light, even in blustery conditions. The sea, in particular, can be very changeable, so when conditions are good, make sunbursts a priority. Even putting them off until the end of the dive can mean missing the peak of the light.

A couple of minor factors worth a quick mention: First, clear air helps. If the sky is hazy with high cloud, humidity or dust then the definition of our sunbursts will diminish. Second, bright tropical sun at midday is harder to work with (because of its sheer intensity) than when the sun is low in the sky. Third, water visibility plays a small role, with rays showing up more clearly in murkier waters, but also penetrating less deep (meaning you have to stay shallow), so I see no need to seek poorer viz.
 

Sun beams under a pier show up well in the murky water. However, the well-defined beams here are the result of the slats in the jetty slicing up the sun, England. (Jetties and pontoons regularly create this effect; see “Splitting the Sun”, below)

Stay Shallow

It is normal to start our dives by descending to the seabed, and for many of us this is so ingrained that we swim down straight past the optimal sunburst conditions—only discovering them as the dive is finishing. The take-home message is: If you want beautiful sunbursts, stay shallow! We will get into the detail below, but 30 feet (10 metres) is a good maximum depth limit for sunbursts. Safety stop depth: 15 feet (5 meters) is often ideal.
 

These images of the sun are taken at the same time, in the same conditions and with the same settings—just at different depths. Note how as depth increases so the sunbeams become less prominent and the sunball develops a cyan halo, Cayman Islands
 

Staying shallow improves both elements of the sunburst: The sunrays are more pronounced and the sunball is more attractive. As we go deeper, sunrays become weaker and less defined, so don’t show up in our pictures. This is because the more water they pass through, the more their light is scattered and diffused. The higher the sun, the calmer the water, and the clearer the visibility—the deeper they can be seen. The sunball is also impacted by depth: In the shallows, it is pure white, but with depth, an ugly cyan halo develops around it. This is caused because the sunlight becomes increasingly blue with depth. When we are deep, the center of the sunball stays white because all color channels are massively overexposed, but the smaller overexposure around the edges only overexposes the blue light, which creates the ugly halo. In short, shallow is good. We can still shoot the sun deeper, and it will provide useful contrast and a focal point, but we won’t get a drop-dead gorgeous sunburst at depth.
 

This is the deepest sunburst photo here. The yellow tube sponge is at 65 feet (20 meters) and the conditions were absolutely perfect—glass calm, clear blue sky, high sun, crystal water—making this shot possible. The sunbeams are still very attractive at this depth, although there is a clear cyan halo around the sun, Cayman Islands
 

The other important factor in controlling the optimum depth for a sunburst photo is the height of the sun in the sky. When the sun is high in the sky, such as in the middle of the day in the tropics, we have the chance to capture beautiful sunbursts deeper, typically down to 30 feet (10 meters), giving us a wider depth range to search for an interesting foreground subject or scene. These are the conditions in which the sun creates symmetrical beams, shining out in all directions, known as radial light.
 

Radial light can be photographed deeper than dappled light, but it can also be captured in the shallows, such as with this marine iguana, Galápagos
 

When the sun is low in the sky, we need to dive much shallower still. A low sun creates dappled light underwater, but this beautiful effect is best seen in the top 9 feet (3 meters). In other words, if you go down even to safety stop depth, you are too deep and will miss the best images. It also means that if we want to shoot dappled light, we need to choose a dive site with subject matter in the top 9 feet (3 meters). Dappled light is warmer colored because the low sun means the light travels through more atmosphere, endowing it with a warmer color. The low angle means it is refracted through different parts of the surface (usually several waves), which separates the golden rays into repeating layers. Dappled light is often described as evening light, but this is the view of a lazy tropical diver! You will find the same attractive light if you get up for dawn or in the middle of the day if you are willing to go diving on a sunny winter’s day at high latitudes.
 

Dappled light is beautiful, but can only be captured very shallow. Seek out dive sites with subject matter right to the surface when shooting it, Egypt
 

Finally, there are two other benefits of being shallow. First, it is easier to keep the sunball out of the frame. People never talk about this, but if you are deeper, you have to shoot up to get beams and inevitably get the sunball, too. If you are shallow, you can frame more horizontally to get the sunrays and can easily keep the sunball out of the top of the picture. Second, being shallow helps to capture a warm color of the sun (which, because of color absorption, gets cooler with depth). This particularly helps get the attractive yellows and oranges of dappled light.
 

Being very shallow makes it easier to keep the sunball out of the frame and captures the warmth of dappled light, Cuba

Managing Dynamic Range

Before tuning our settings for the sunburst, there is another factor that probably has a bigger say in the success of our shot—the exact composition we are asking our camera to capture. Cameras can only capture a finite range of brightnesses and if we ask too much, they will struggle and our pictures won’t be as attractive as we want.
 

Presenting the camera with a manageable range of brightness makes it easier for it to capture attractive pictures and features like sunbeams, Malaysia
 

The most important part of a sunburst are the sunbeams, and these are always my priority in framing and exposure. If we want these rays to show up clearly in our pictures, we need to expose for them. The brighter we make them, the more they show up. The challenge is that the sunball is always brighter than the sunbeams, and rather than trying to find some compromise camera settings to capture both, if is often better to hide the sunball from the camera, so we can expose for the sunbeams.

We can exclude the sunball by leaving it out of the frame, hiding it behind part of the reef, scenery or dive boat, or even place it behind the subject. We can then choose settings (usually a slower shutter speed) to correctly expose the rays, so they show up strongly in the picture.
 

The subject, an Australian sea lion, hides the sunball, making it possible to expose for the sunbeams, Australia
 

A couple of practical tips: First, if planning to shoot the sun behind a moving subject (like, say, a turtle), we can get the settings right before approaching, by aiming the camera at the sun and then blocking the sunball with our hand (as we hope the subject will) to check the exposure of the beams. When shooting scenery, look for subjects in the shadow of a reef outcrop or in the shadow of the boat. Then, when you frame them up, you will find that the sun is hidden. A subject near the edge of the shade should give the best beams.
 

This sea fan was in the shade—but only just—making it an ideal subject to photograph with sunbeams, while avoiding the sunball, Indonesia

Settings

Contrary to many articles and books, there are no specific settings for capturing a beautiful sunburst. But that does not mean that camera settings are not important—they are critical. The sun is the brightest subject we can photograph, so it is likely that sunburst images will require a fast shutter speed, small aperture and low ISO. But far more important than specific numbers for each is choosing an exposure that is correct.

It is said in many places that a fast shutter speed helps to freeze sunbeams into clearly defined rays. This is true, but not especially important. Sunrays are usually bright, but in situations when the beams are dark (in the evening and in caverns), they will not show up at all with a fast shutter speed and will only show when you expose correctly for them, even if this means a slow shutter speed.
 

In this dark cenote, I used a slow shutter speed of just 1/25s, and the sunbeams are still well defined (and correctly exposed), Mexico
 

We regularly want to shoot sunbursts with foreground flash illuminating a subject in front of the sun. With flash, our shutter speed is limited by the camera’s flash synchronization speed. This is usually something like 1/250s and is sometimes not enough to stop a sunburst overexposing. In this situation, we must also lower the ISO and close the aperture of the camera to bring the sunburst exposure into range. The downside of adjusting ISO and aperture is that these impact on a flash exposure, so we typically have to turn our strobes to higher settings.
 

Sunburst and coral, shot at fastest sync speed, fully closed aperture, low ISO and strobes on full power, Palau
 

In the brightest conditions, we often find we run out of strobe power for the reef when shooting sunbursts, because the exposure settings required to correctly expose the sun mean that our flashes are not powerful enough to light the scene. The best solution in the moment (without going shopping and buying more powerful strobes) is to select a smaller foreground subject and get closer to it, allowing more strobe light to reach the subject.

There is a new solution to this conundrum in the world of underwater photography and that is high speed sync (HSS), which when using certain flashes allows us to exceed our flash synchronization speed. However, HSS is no free lunch, as it does reduce the flash power a little, but it is a useful tool in this regard. The final solution to mention is to time your dives towards the end of the day when the sun is less intense and it is easier capture without such extreme settings. Sunbursts are often more attractive at these times, too.
 

Using high speed sync (HSS) enabled strobes (Retra Pro), I could shoot this jellyfish and sunburst at 1/500s, England

Camera Tech

In the early days of digital cameras, there was a big difference between how well slide film and digital sensors could capture sunbursts. Slide film handled overexposure better, allowing us to expose for the sunbeams without the sunball dominating the picture. Over the last 20 years, the dynamic range that digital sensors can record has grown and grown. Initially, there were clearly some digital cameras that were better than others. But for the last decade, photographers have shown that all digital cameras can capture beautiful sunbursts in good conditions. The best cameras will do a marginally better job, but these days, everyone has the capability to shoot beautiful sunbursts underwater. Most photographers who tell me their camera cannot shoot good sunbeams are invariably trying to shoot the sun in poor conditions or from too deep.
 

Most modern cameras do a good job of capturing the sun underwater and we can use it freely in our images, Cuba

Sunburst Double Exposures

In many locations around the world, the scenery and the subjects start much deeper than the depth that beautiful sunbursts can be captured. The Mediterranean is a particularly obvious example, where the sun dances through a calm surface all summer, but the colorful marine life is predominantly below 100–130 feet (30–40 meters). The Mediterranean is also home to Fotosub-style on-the-day photography competitions, where images must be submitted direct from the camera.

A popular solution to overcome the depth problem is the double exposure, where the photographer shoots a beautiful sunburst at the top of the frame without flash, and then at depth shoots colorful marine life in the bottom of the frame against a black background. When these images are combined in camera, it gives a new RAW file with colorful deep water life set against an attractive sunburst. 
 

A double exposure of a golden crinoid and a sunburst, through trees, Indonesia

Flares and Reflections

Shooting into the sun can sometimes create lens flare and internal reflections inside the port. Water contact lenses and teleconverters are often more prone to lens flare. Flare isn’t always a bad thing in images, especially in moving images, as it adds atmosphere to a shot. Internal reflections are more problematic with dome ports, especially with certain dome/lens combinations, and can be so bad that you can read all the lens information in the final picture reflected in the dome! You can use a black sharpie pen to cover up bright lettering on your lens, or even use telescope flocking tape to conceal offending items. Fortunately, both these issues can be seen while shooting, and if you know your system is prone to flare and reflections then keep an eye on it, as a small change in composition will greatly reduce the problem. Finally, dome port scratches tend to show up most clearly when shooting into the sun. First, try and avoiding scratching your dome! If you do have a scratch on a trip, rotate the dome so the scratch is at the bottom of the picture, so the sun does not catch it.
 

Flare can occur when shooting into the sun, England. A small change in composition can hide it. Alternatively, go all J.J. Abrams and embrace it!

Splitting the Sun

As discussed above, it is often advantageous to hide the sunball from the camera. When we do this using subject matter above the surface, such as a tree or a jetty, we have the chance to split the sun, creating eye-catching clearly-separated beams. In short, the more beams we have, the more attractive the sunburst looks, so this is usually a good effect to chase.

When photographing dappled light, it can help images to time shots to when the sun is split into layers by the waves. I tend to find that when I am shooting these pictures, I try and get into the rhythm of the waves to help me time my click for the most attractive light. When photographing a distant model in front of the sun, it can be effective to use them to split the rays.
 

Mangrove trees have split the sun into clearly defined rays, giving dramatic light, Cuba

Downward Rays

In calm conditions, with high sun, we can also shoot sunrays looking straight down into the water. These photos typically work best looking down into deep water, as the plain blue background shows off the beams best. These shots are straightforward to shoot, but benefit from additional contrast in processing (such as dehaze). In very calm conditions, your own shadow will be clear in the image—so curl up into a ball before shooting to hide your recognizable shape!
 

Downward sunrays look best in deep open water and can look attractive even without a subject. Symmetrical compositions usually look best, Sri Lanka

Lens Starburst

I have debated including this final point, as it can cause confusion, but I reckon if you have made it this far, you will be fine! A starburst is a lens effect caused by lens diffraction on a distant light source, turning a light point into a star. A starburst looks different to a sunburst, as it has a small central ball and very symmetrical rays that are of equal length. The more we close the aperture, the more pronounced the effect. It is also worth noting that different lenses give different effects, as the number of aperture blades impacts on the look of the starburst, with specific lenses always recording starbursts with the same number of rays.

Although I have not tested this thoroughly myself, I don’t believe that the starburst effect can be achieved in a normal underwater photo of the sun, perhaps because the sun no longer becomes a point of light as it refracts on an angle through the surface. Therefore, I don’t believe there is a need to choose specific lenses or use closed apertures specifically to try to create a starburst underwater, when shooting sunbursts. Underwater sunbursts are created by the surface of the water splitting the sunlight into focused beams, and to my eye are more beautiful and certainly more varied than above-water starbursts.
 

A starburst photo (taken above the surface) of the sun and frigate bird. This is a lens effect, turning a point of light into a star, and is not the same as an underwater sunburst, Galápagos
 

About Alex Mustard: Alex is a professional underwater photographer with a Ph.D. in marine ecology and is well known as the author of Underwater Photography Masterclass. His pictures have won many awards and have featured in 14 different books of winning images from the prestigious Wildlife Photographer of the Year competition. Alex teaches underwater on popular workshops in the best diving destinations around the world. Check out more of his amazing work or join one of his workshops at www.amustard.com.
 

Alex Mustard selfie with the rarely seen British sunburst, taken for this article with high speed sync (HSS) flash at 1/800s!