Underwater Color Correction Filters: Why & How?

If you’ve ever reviewed your underwater photos only to find them disappointingly blue or green, you’re not alone. This color loss is a natural effect of how water absorbs light, a fascinating scientific process we explored in our article on the science behind why colors disappear underwater. But understanding why it happens is only half the battle. The good news is that physical color-correcting filters offer a straightforward and effective method to reclaim those lost hues, especially when you’re relying on the sun’s natural, or ambient, light. This guide is your key to choosing and using these filters effectively with your DIVEVOLK smartphone housing to bring back the vibrant underwater world to your images.

And at DIVEVOLK, we have a specialized range of filters designed exactly for these challenges. Here's the DIVEVOLK filters guide.

1. Your Color Correction Toolkit: Red, Magenta, and Pink Filters Explained

To counteract the color imbalances caused by light absorption underwater, photographers and videographers turn to physical color-correcting filters. These simple yet effective tools can dramatically improve the vibrancy and accuracy of underwater imagery captured using ambient light.

How Physical Filters Work: The Subtractive Principle

It’s a common misconception that colored filters add missing colors back into an image. In reality, they operate on a subtractive principle. These filters work by selectively absorbing or blocking some of the dominant blue or green light that overwhelms the underwater scene. By reducing the intensity of the overly prevalent cool colors, the filters allow the remaining warmer colors (reds, oranges, yellows – those that haven’t been completely absorbed by the water yet) to be more accurately recorded by the camera’s sensor. This process helps the camera achieve a more natural and balanced white balance, leading to images that more closely resemble the true colors of the underwater environment. If red light, for example, is entirely absent at a certain depth, a red filter cannot magically recreate it; it can only enhance the red light that is still present, however faintly.

Red Filters

• Purpose: Red filters are specifically designed to correct the pervasive blue color cast typically encountered in clear, blue saltwater environments, such as tropical seas and coral reefs. DIVEVOLK offers a high-quality Red Filter with a 67mm thread ideal for these conditions.
• How they help: By filtering out a significant portion of the excess blue light, red filters allow the reds, oranges, and yellows—which are still present at certain depths but are masked by the dominant blue—to become more prominent and visible in the final image or video footage.

Magenta Filters

• Purpose: Magenta filters are the tool of choice for correcting the greenish color cast often found in waters with higher concentrations of algae, certain minerals, or particulate matter. This includes many freshwater lakes, quarries, temperate ocean waters with kelp forests, or even some coastal saltwater areas experiencing algae blooms. DIVEVOLK’s Magenta Filter, also with a 67mm thread, is designed for these environments.
• How they help: Magenta filters work by absorbing excess green and cyan light. This subtraction helps to restore a more natural color balance, allowing warmer tones like reds and oranges to be more faithfully rendered.

Pink (Snorkel) Filters

• Purpose: Pink filters, sometimes referred to as snorkel filters, are essentially a lighter or less intense version of a red filter. They are designed for use in very shallow water, typically ranging from 2 to 25 feet (approximately 0.6 to 7.5 meters), depending on the specific filter and water clarity.
• How they help: In shallow depths where red light loss is present but not extreme, a full-strength red filter can be too powerful, leading to images that appear overly red or unnatural. Pink filters provide a milder color correction suitable for snorkeling or diving just beneath the surface, subtly enhancing warm tones without overcorrection. The existence of such filters highlights that color correction is a nuanced process; too much correction can be as detrimental as too little.

To simplify selection, the following table provides a general guide:

Table 1: Filter Selection Guide

Filter Type	Typical Water Color/Environment	Optimal Depth Range (Ambient Light)	Primary Purpose
Red	Blue, clear saltwater (tropical, reefs)	~15-80 ft / 5-25 m	Corrects blue cast, enhances reds, oranges, yellows
Magenta	Green water (freshwater, algae, kelp)	~15-80 ft / 5-25 m	Corrects green cast, enhances warmer tones
Pink (Snorkel)	Blue or clear water, very shallow	~2-25 ft / 1-7.5 m	Mild correction for slight red loss near surface

2. Mastering Your Filters: Tips for Vibrant Underwater Shots

Simply attaching a filter is only the first step; using it effectively requires an understanding of optimal conditions and techniques. Effective filter use is an active process, demanding attention to depth, water conditions, and camera settings, rather than a passive “set and forget” approach.

Finding the “Golden Zone”: Optimal Depth Ranges

Color-correcting filters are most effective within a specific depth range, often referred to as the “golden zone”. For typical red and magenta filters, such as those offered by DIVEVOLK, this range is generally between 10 to 15 feet (approximately 3 to 5 meters) at the shallow end, extending down to about 80 feet (approximately 25 meters) at the deeper end.

• Too Shallow (e.g., <10-15 feet / 3-5 meters): In very shallow water, there often isn’t enough color loss to warrant a strong filter. Using a standard red or magenta filter here can result in images that are unnaturally and overly tinted with the filter’s color. In these conditions, a lighter pink/snorkel filter is more appropriate, or one might rely solely on the camera’s white balance settings.
• Too Deep (e.g., >80 feet / 25 meters): As depth increases, ambient light diminishes significantly, especially the warmer wavelengths. Beyond a certain point, there is simply insufficient red, orange, or yellow light remaining for the filter to enhance. Using a filter in such conditions will primarily result in a darker image that still lacks vibrant colors. At these greater depths, artificial light sources like strobes or video lights become essential for restoring color.

This “golden zone” represents a balance: there must be enough color aberration caused by the water for the filter to correct, but also enough of the specific light wavelengths (e.g., red light for a red filter) remaining in the ambient light for the filter to effectively work with and enhance.

The Crucial Role of White Balance (WB)

Physical filters play a vital role in helping the camera achieve a more accurate white balance underwater. However, relying on Auto White Balance (AWB) alone, even with a filter, may not yield the best results, as AWB systems can still be confused by the unusual filtered light.

• Custom White Balance is Key: For optimal color accuracy, it is strongly recommended to use your camera’s custom white balance feature with the filter attached.
  • Procedure: To set a custom white balance, point the camera (with the chosen filter already mounted) at a white or neutral gray object (like a diver’s slate or a patch of white sand) at the intended shooting depth and in the same lighting conditions as your subject. Then, follow your camera’s instructions to capture this reference and set it as the custom white balance. This action effectively “tells” the camera what “white” should look like under the current filtered ambient light conditions.
  • Frequency of Adjustment: Because the quality and color of ambient light change with depth and varying conditions (e.g., sun obscured by clouds), it’s advisable to reset your custom white balance whenever you change depth by approximately 10-15 feet (3-5 meters), or if you notice a significant shift in the ambient lighting.
• Alternatives if Custom WB is Unavailable: If your camera lacks a custom white balance function, preset modes like “Underwater” (if available) or “Cloudy” can sometimes offer a slight improvement by warming the image, though these are generally less precise than a custom setting.

The combination of a physical filter and a correctly set custom white balance is synergistic. The filter pre-conditions the light by reducing the dominant cool cast, making it easier for the custom white balance to then fine-tune the colors and render them more accurately than either method could achieve alone in challenging ambient light conditions.

Shooting Techniques for Best Filter Results

Beyond depth and white balance, certain shooting techniques can maximize the effectiveness of your filters:

• Shoot with the Sun at Your Back: Position yourself so that the sun is behind you, illuminating your subject as directly as possible. This ensures the maximum amount of ambient light reaches your subject, providing more light for the filter to work with and for your camera to capture.
• Get Close to Your Subject: This is a fundamental rule in underwater photography for several reasons, but it’s especially critical when using filters. Minimizing the distance between your lens and the subject reduces the amount of water the light has to travel through, thereby lessening color filtration and light loss before the light even reaches your filter and lens.
• Angle the Camera Slightly Downwards: Pointing the camera at a slightly downward angle can sometimes help to take better advantage of the available overhead sunlight.

When to Attach and Remove Filters During a Dive

Knowing when to add or remove your filter during a dive is also important:

• Attachment: Attach the appropriate filter (red for blue water, magenta for green water) before you descend into its optimal working depth range, for example, once you pass the initial 10-15 feet where color loss becomes more pronounced. DIVEVOLK’s filters are designed with water inlet ports along the edge, which allow water to quickly flood the gap between the filter and the lens port upon submersion, effectively eliminating trapped air bubbles that could otherwise mar your shots.
• Removal: Remove the filter if you ascend into very shallow water where its corrective effect is no longer needed or could cause an undesirable color cast. Critically, filters should also be removed if you switch to using artificial lights (strobes or video lights) as the primary source of illumination for your subject.

3. Gearing Up: Mounting Filters on Your DIVEVOLK Housing

For users of DIVEVOLK smartphone housings, attaching color-correcting filters is a straightforward process, thanks to a well-thought-out accessory system. The 67mm thread has become a common standard in underwater photography for attaching wet lenses and filters, offering a degree of flexibility.

DIVEVOLK Housing Filter Compatibility

DIVEVOLK housings, particularly popular models in the SeaTouch series like the SeaTouch 4 Max, are designed to accommodate external lenses and filters typically through a 67mm threaded lens adapter. DIVEVOLK manufactures its own line of red and magenta color-correcting filters, which are conveniently available with this standard 67mm thread, ensuring seamless integration. You can explore the full range of DIVEVOLK lenses and filters here.

Mounting Options for DIVEVOLK Housings

There are a couple of primary ways to attach these 67mm filters to a DIVEVOLK housing:

1. Direct Attachment to a 67mm Lens Adapter Port: If your DIVEVOLK housing is equipped with an integrated 67mm threaded lens adapter port directly on the housing body or lens window, the filter can often be screwed on directly to this port.
2. Using the DIVEVOLK Expansion Clamp with Lens Adapter: DIVEVOLK offers an accessory called the “Expansion Clamp with Lens Adapter” (or similar “67mm adapters arm” found within their dive accessories). This clamp is designed to attach to the SeaTouch 4 Max housing (and potentially other models) and provides a secure 67mm threaded mount point.
   • Installation of the Clamp: The expansion clamp typically attaches to the housing using M6 threaded mounts on its top and 1/4-inch threaded mounts on its bottom, ensuring a stable connection. This clamp system is part of a modular approach, allowing for the attachment of various accessories, including lenses, filters, lights, and trays, making the housing a versatile platform.
   • Filter Attachment: Once the expansion clamp with its 67mm adapter is installed, the filter simply screws onto this provided 67mm thread.
     A similar accessory, the “Divevolk Lens Holder,” which includes an expansion clamp and a 67mm holder and arm, serves the same purpose for mounting 67mm threaded accessories.

Step-by-Step Filter Attachment Guide

While specific steps might vary slightly based on the exact DIVEVOLK housing model and adapter used, the general process for attaching a 67mm filter is as follows:

1. Preparation: Ensure your DIVEVOLK housing is equipped with the necessary 67mm lens adapter port or has the DIVEVOLK Expansion Clamp with 67mm thread securely installed.
2. Alignment: Carefully align the threads on the 67mm filter with the corresponding threads on the housing’s adapter or the expansion clamp’s adapter.
3. Attachment: Gently rotate the filter clockwise, screwing it onto the adapter. Ensure the filter is snug and secure, but avoid overtightening, as this can damage the threads on either the filter or the adapter, or make the filter difficult to remove later.
4. Verification: If possible, test the fit on land to ensure the filter is securely attached before entering the water.

Ensuring a Secure, Bubble-Free Fit

A common frustration with underwater filters can be trapped air bubbles between the filter and the housing’s lens port, which can appear as distracting blobs in photos or videos. DIVEVOLK has addressed this by incorporating “water inlet ports” along the edges of their newer filter designs. These ports allow water to quickly and efficiently flood the space between the filter and the lens port as soon as the housing is submerged, effectively eliminating trapped air. This thoughtful design feature enhances usability, particularly for those newer to underwater photography who might not otherwise think to check for or clear such bubbles. If using a filter without these specialized ports, it’s good practice to briefly submerge the housing and tilt it in various directions once underwater to allow any trapped air to escape from behind the filter before commencing photography or videography.

Maintenance

As with all underwater photography equipment, proper maintenance is key to longevity and performance. After each dive, it’s important to thoroughly rinse both the filter and the DIVEVOLK housing (with the filter attached or separated) in fresh, clean water to remove salt, sand, and other residues. Allow them to air dry completely in a shaded area before storage.

4. Beyond Filters: Understanding Limitations and Alternatives

While physical color-correcting filters are invaluable tools for ambient light underwater photography and videography, they are not without limitations, nor are they the only solution for achieving vibrant underwater colors. Understanding these constraints helps in choosing the right approach for different situations.

Limitations of Physical Filters

• Light Reduction: A significant characteristic of color filters is that they inherently reduce the total amount of light reaching the camera’s sensor. This light loss can be equivalent to 1 to 1.5 f-stops or more. To compensate, photographers may need to use slower shutter speeds (risking motion blur), wider apertures (reducing depth of field), or higher ISO settings (potentially introducing digital noise), especially in already dim underwater environments.
• Ineffectiveness at Extreme Depths: As previously discussed, filters rely on the presence of some residual warm-wavelength light to enhance. At significant depths (often beyond 30-80 feet, depending on water clarity and filter strength), so little of this light remains that filters become ineffective and will merely darken the image further without improving color.
• NOT for Use with Primary Artificial Lights (Strobes/Video Lights): This is a critical point for users to understand. If strobes or video lights are being used as the primary source of illumination for the subject, a color-correcting filter should not be used on the camera lens. Artificial lights are designed to provide a full spectrum of light, effectively restoring all colors to the subject within their operational range. Placing a colored filter in front of the lens would incorrectly alter the color of this balanced artificial light, often resulting in the subject appearing excessively red or magenta.
• Potential Autofocus Issues: The reduction in light caused by filters can sometimes make it more challenging for a camera’s autofocus system to lock onto subjects accurately and quickly, especially in lower contrast situations.
• Fixed Correction: A physical filter applies a uniform level of color correction across the entire image. This may not be ideal for scenes that contain elements at significantly different distances from the camera, as the degree of color loss (and thus the required correction) will vary for near and far objects.

Brief Overview of Alternatives

When physical filters are not suitable or sufficient, other methods can be employed to achieve accurate underwater colors:

• Artificial Lights (Strobes and Video Lights):
  • Pros: These are often considered the optimal solution for restoring the full spectrum of colors to underwater subjects, regardless of depth (within the light’s effective range). They add punch, contrast, and sharpness to images and are essential for deeper dives, night dives, or illuminating subjects in crevices or overhangs.
  • Cons: The effective range of artificial lights is typically limited to a few feet. They can add bulk and expense to a camera setup and require learning proper lighting techniques to avoid issues like backscatter.
• Post-Processing (Editing Software):
  • Pros: Modern editing software offers powerful tools for color correction and white balance adjustment after the dive. If images are captured in a RAW file format, there is considerable flexibility for adjustment.
  • Cons: Post-processing cannot magically “add back” color information that was never captured by the sensor in the first place, especially with heavily compressed JPEG images or 8-bit video files commonly produced by smartphones and action cameras. Attempting to push colors too aggressively in editing can lead to undesirable artifacts, noise, or banding. For smartphone users, such as those with DIVEVOLK housings who are often working with JPEGs or compressed video, getting the color as accurate as possible “in-camera” with the aid of a filter is often more beneficial than relying heavily on post-production fixes.
• Camera White Balance (Without Filter):
  • Pros: This method requires no additional equipment and can be effective in very shallow, clear water where color loss is minimal.
  • Cons: The effectiveness of camera white balance alone is severely limited beyond very shallow depths, as the camera’s adjustment range may not be sufficient to compensate for the significant loss of warm colors.

The choice of color correction method ultimately involves a trade-off between convenience, cost, desired image quality, and the specific shooting conditions encountered. Often, as photographers gain experience, they may employ a combination of these techniques.

Table 2: Color Correction Methods: Quick Comparison

Method	Pros	Cons	Best Use Cases
Physical Filters	Simple to use, improves color in-camera, aids white balance, relatively inexpensive.	Reduces light, applies fixed correction, depth-limited, not for use with primary strobes/video lights.	Ambient light photography/videography with DIVEVOLK filters at shallow to moderate depths (e.g., 15-80ft / 5-25m).
Artificial Lights	Restores full color spectrum, effective at any depth (within light’s range), adds contrast and sharpness.	Limited range, can be bulky/expensive, requires skill to use effectively, potential for backscatter.	Macro photography, close-focus wide-angle shots, night dives, deeper dives, primary subject illumination.
Post-Processing	High degree of control over adjustments, can correct minor color casts, powerful tools available, especially with RAW files.	Cannot recover completely lost color information, risk of artifacts with JPEGs/8-bit video, time-consuming, requires skill.	Fine-tuning images, correcting minor casts, particularly beneficial when shooting in RAW format.
Camera WB (Alone)	No extra equipment needed, quick to apply.	Limited effectiveness beyond very shallow water, camera-dependent adjustment range.	Very shallow depths (e.g., <10ft / 3m), exceptionally clear water, casual shooting.

5. Conclusion: Capturing the True Colors of the Underwater World with DIVEVOLK

The journey to capturing vibrant and true-to-life underwater photographs and videos begins with an understanding of how the aquatic environment uniquely alters light. Physical color-correcting filters, specifically red filters for blue saltwater and magenta filters for greener waters, offer an accessible and effective means to counteract this phenomenon when relying on ambient light.

For users of DIVEVOLK housings, the integration of 67mm threaded filters is a straightforward process, enhancing the capabilities of their smartphone camera systems. The key to success with these filters lies not just in their attachment, but in their intelligent application: using them within their optimal depth ranges—typically between 15 and 80 feet (5 to 25 meters)—and, crucially, pairing them with a correctly set custom white balance. This combination allows the camera to more accurately interpret the filtered light and record the scene with a richer, more natural palette. For a comprehensive look at DIVEVOLK’s filter solutions, visit our Dive Filter Guide.

While filters are powerful allies, they are part of a broader toolkit. Recognizing their limitations, such as light reduction and ineffectiveness at extreme depths or with artificial lights, is as important as knowing when to use them. Successful underwater imaging is a blend of understanding the science of light, knowing the capabilities and limitations of the equipment, and applying sound photographic techniques, like getting close to the subject and shooting with the sun.

Ultimately, by embracing these tools and techniques with your DIVEVOLK gear, and through practice and experimentation, underwater photographers and videographers can significantly reduce the frustration of washed-out colors and instead bring home images that truly reflect the breathtaking beauty and vibrant life witnessed beneath the waves.