Quick Answer: Water absorbs light by wavelength, and it removes red first. By around fifteen feet, most red is gone; by thirty, orange has followed. Your brain corrects for this in real time and your camera does not, so it records the physically accurate blue cast your eyes edited out. The fixes are getting closer, staying shallower, shooting in bright overhead light, and correcting colour afterwards — not a better camera.

Distance through water is the single variable that matters most.

Why does water take the colour out?

Because water absorbs different wavelengths at very different rates, and the warm end goes first.

Light travelling through water loses energy as it goes, and the loss is not even across the spectrum. Red is absorbed fastest — a large proportion is gone within the first fifteen feet or so. Orange follows, then yellow. Blue and green penetrate much further, which is why deep water looks blue rather than dark.

The critical point is that this applies to the whole light path, not just depth. Light travels from the surface down to the subject, then from the subject back to your mask or lens. A fish twelve feet away horizontally at a depth of six feet has as much water in its light path as one directly below you at eighteen. This is why distant subjects look washed out even in shallow water, and it is the single most useful thing to understand.

There is a second effect layered on top. Suspended particles scatter light, reducing contrast and adding haze exactly as fog does in air. More distance means more scattering as well as more absorption, so the two problems compound.

Your visual system does something the camera does not. Colour constancy is the process by which your brain interprets colour relative to context rather than absolutely, and it is remarkably good at it. It knows what the coral should look like and adjusts. You genuinely perceive more colour than reaches your eye.

The camera records what arrives. Both are correct, and only one matches your memory.

Does getting closer really make that much difference?

It is the difference between a photograph worth keeping and one you delete, and the effect is much larger than most people expect.

Halving the distance to your subject roughly halves the water in the light path, which means dramatically less absorption and less scattering at the same time. There is a well known rule of thumb among underwater photographers that you should get as close as you can and then get closer, and it exists because nothing else in the process comes near it for impact.

Practically, anything beyond about six feet is going to look blue and flat, no matter what equipment you have. Under three feet, colours start surviving. Under eighteen inches, with good light, you can get genuinely accurate colour with no filter or flash at all.

This reframes the whole activity. Wide scenic shots of a reef, the ones everyone tries first, are the hardest possible photographs to take and the ones that disappoint most reliably. Close subjects — a single coral head, a sea fan, a fish that will tolerate approach — are both easier and better.

Getting close has its own discipline:

Approach slowly and horizontally. Fish respond to speed and to being loomed over from above. A slow, level approach gets you far nearer than a direct descent.

Stay still and let them come. Many species will approach a stationary snorkeller within a minute or two and will flee from someone actively chasing.

Never touch or stand on coral. It is fragile, it is alive, and contact damages it. Reef safety and reef etiquette matter more than any photograph.

Breathe and hold position at the surface rather than repeatedly diving. Most good snorkelling shots are taken from the surface or just below it, where the light is strongest.

What about light, timing, and the surface?

Light is the second variable, and it is almost entirely a matter of when you get in the water rather than what you do once you are there.

The sun needs to be high. Between roughly ten in the morning and two in the afternoon, light enters the water at a steep angle and penetrates efficiently. Early and late, most light is reflected off the surface rather than entering it, which is why the same reef looks vivid at midday and dull at four.

Clear, bright days beat overcast ones by a wide margin. Cloud cover reduces the amount of light entering the water and removes the shafts and dappling that give underwater images their depth.

Calm surface conditions matter more than people expect. A choppy surface scatters incoming light and reduces what reaches your subject, as well as making it much harder to hold position.

Shoot with the sun behind you. Sunlight coming over your shoulder illuminates the subject; shooting toward the sun gives you a silhouette and heavy backscatter.

Angle upward slightly where you can. Shooting downward gives you a subject against a background of sand or rock, both of which are dull. Shooting slightly upward puts the subject against bright water or the surface, which has far more life to it.

Avoid using the built in flash for anything beyond about a foot. It illuminates every suspended particle between the lens and the subject, producing the white speckled backscatter that ruins so many underwater photos. Close macro subjects are the exception.

Water clarity itself is worth checking rather than assuming. Visibility drops after rain and swell, as runoff and stirred sediment enter the water, and a site that was superb two days ago can be poor today for reasons that have nothing to do with your technique. Locals and dive shops know, and asking takes a moment.

Do filters and settings actually help?

Some do, within a narrow band of conditions, and it is worth knowing which is which before spending anything.

Red filters work at moderate depth in blue water and nowhere else. A red or magenta filter compensates for absorbed wavelengths by cutting the blue, and in the range from roughly six to fifty feet in clear tropical water they can transform a photo. Above about six feet they overcorrect and give everything a pink cast, and in green water a red filter is the wrong colour entirely — those need magenta.

The important limitation: a filter cannot restore light that is not there. If red has been fully absorbed at your subject’s distance, filtering the remaining blue just makes a darker, still colourless image. This is the same conclusion as before — get closer first.

White balance beats filters if your camera allows manual setting. Setting white balance manually against a neutral surface at your working depth is more accurate than any fixed filter, and it can be redone as conditions change. Many action cameras have an underwater mode that does an approximation of this automatically.

Shoot in RAW if the camera supports it. RAW files retain the data needed to recover colour in editing, and JPEG processing discards a lot of it. Most disappointing snorkelling photos are recoverable to a surprising degree in editing, particularly if you shot in shallow, bright conditions.

A basic edit does most of the work. Increase temperature toward warm, add a little magenta, lift contrast, and reduce blue saturation slightly. Two minutes per photo, and it closes most of the gap between what the camera recorded and what you remember.

Keep the housing lens spotless and free of bubbles. A film of sunscreen or a bubble sitting on the port softens the whole frame, and it is the most common avoidable technical fault. Rinse the housing and wipe the port before entering.

How does this change as the season turns?

Considerably, and in ways that affect both what you can photograph and how comfortable you are doing it.

Sun angle drops as autumn progresses, which means less light entering the water and a shorter useful window each day. The midday window that ran from about ten to two in midsummer contracts noticeably, so timing matters more now than it did in July.

Water clarity often improves in early autumn in many temperate locations, as summer algae blooms subside and the water cools. This partly offsets the light loss, and in some places early autumn is genuinely the best visibility of the year.

Water temperature lags air temperature by weeks. Late summer and early autumn water is often still comfortable long after the air has cooled, which surprises people who assume the season is over. A thin wetsuit or a rash guard extends the workable season substantially, and being cold is the fastest way to ruin both your patience and your breath control.

Storm and swell frequency rises, which affects both safety and visibility. Checking conditions rather than assuming has more value now than in a settled summer week.

Some practical seasonal points:

Go earlier in the day than you did in summer, since the high sun window shifts and shortens.

Expect different marine life. Seasonal movement means some species leave and others arrive, so a familiar site is genuinely a different subject in September than in June.

Rinse gear more diligently as trips become occasional. Kit that sits in a bag for a month with salt on it deteriorates, and masks and fins are the ones that suffer.

A safety note, and it is the important one: snorkelling in cooler water, shorter daylight, and less settled conditions carries more risk than the same activity in midsummer. Never snorkel alone, tell someone where you are going, use a float or buoy where appropriate, be honest about currents, and get local advice about the site. This is general information about photography and conditions, not safety training, and no photograph is worth being somewhere you should not be.

Myth vs Fact: Underwater Photography

Myth: you need a better camera. Fact: distance to subject, depth, and light outrank equipment by a large margin. A phone in a decent housing at eighteen inches beats an expensive camera at eight feet, every time.

Myth: a red filter fixes underwater colour. Fact: it helps within a specific depth range in blue water and actively hurts in shallow water or green water. It is a correction for a particular problem, not a general improvement.

Myth: the flash will bring the colours back. Fact: the built in flash lights up suspended particles and produces backscatter at anything beyond very close range. Natural light plus proximity is better for almost all snorkelling.

Myth: overcast days are fine because there is less glare. Fact: less light entering the water means less colour and less contrast at depth. Bright and high sun is what you want.

Myth: what you saw is what a good photo would show. Fact: your brain performed substantial colour correction in real time. The photo you want is closer to your memory than to the raw optical reality, which is exactly why editing is legitimate rather than cheating.

FAQ: Snorkelling Photo Questions, Answered

Why do my photos look blue even in shallow water?

Almost always because of horizontal distance. The water in the light path includes the distance from you to the subject, not just depth, so a subject ten feet away in six feet of water has plenty of water absorbing red.

Is it worth buying a red filter?

Only if you are regularly shooting in clear blue water below about six feet. In very shallow water it overcorrects, and in green water you need magenta instead. Manual white balance is more flexible if your camera offers it.

What is the best time of day to snorkel for photos?

Mid morning to early afternoon, when the sun is high enough to penetrate rather than reflect. That window narrows as autumn progresses, so go earlier than you would have in midsummer.

How do I get close to fish without scaring them?

Move slowly, approach horizontally rather than from above, and then stay still. Most fish will tolerate a motionless snorkeller far closer than a moving one, and chasing never works.

Can I fix the colour afterwards?

Usually, and more than you would expect. Warming the temperature, adding magenta, and lifting contrast recovers a great deal, especially from shallow, bright shots and from RAW files.

TL;DR:

• Water absorbs red first, and the whole light path counts, so horizontal distance washes out colour as effectively as depth does.
• Your brain colour corrects in real time and the camera does not, which is why the photo does not match the memory.
• Getting closer is worth more than any equipment: under three feet, colours survive; beyond six, nothing helps much.
• Shoot between mid morning and early afternoon, sun behind you, angled slightly upward, and skip the built in flash.
• Filters help only in a specific depth range in blue water; a two minute edit recovers most shots regardless.

On your next swim, pick one subject and get twice as close as feels necessary. That single change fixes more photos than everything else combined.