Neutral Density (ND) filters are an essential tool for photographers and videographers, allowing greater control over exposure and creative effects. Whether you're shooting long-exposure landscapes, silky-smooth waterfalls, or cinematic videos, an ND filter can dramatically improve your results. In this guide, we’ll cover everything you need to know about ND filters, including their differences from CPL and OD filters, whether they’re worth investing in, and which ND filter is best for sunny conditions.

What is an ND Filter and How Does It Work?

An ND (Neutral Density) filter is a piece of darkened glass or resin that reduces the amount of light entering your camera lens. Unlike a CPL (Circular Polarizer) filter, which enhances contrast and reduces reflections, an ND filter evenly cuts down light without affecting color. This allows you to:

• Use longer exposure times without overexposing your image

• Shoot with a wider aperture for a shallower depth of field in bright conditions

• Capture motion blur effects, such as streaking clouds or smooth water

• Maintain the cinematic 180-degree shutter rule in videography

ND filters come in fixed strengths (e.g., ND8, ND16, ND32) and variable versions, where you can adjust the density as needed.

ND Filter vs. CPL Filter – Which One Should You Choose?

A CPL filter is designed to reduce glare and reflections while enhancing color saturation, making it ideal for shooting through glass, water, or in hazy conditions. An ND filter, on the other hand, is primarily used to control light exposure.

When to use an ND filter:

• Shooting long-exposure landscapes or motion blur effects

• Capturing smooth water or cloud movements

• Keeping video shutter speed balanced for a natural look

When to use a CPL filter:

• Enhancing sky contrast in landscape photography

• Reducing reflections on water or glass

• Eliminating haze for sharper, clearer images

For a versatile solution, consider the Freewell V2 Hybrid VND & CPL, which combines both filter types into one adjustable system.

ND Filter vs. OD Filter – What’s the Difference?

ND filters and Optical Density (OD) filters are often confused, but they serve slightly different purposes. Optical Density (OD) refers to the measurement of light absorption, with higher OD values indicating stronger light reduction.

• ND2 = OD 0.3 (1-stop light reduction)

• ND8 = OD 0.9 (3-stop reduction)

• ND64 = OD 1.8 (6-stop reduction)

Understanding these values helps photographers choose the right filter strength for different lighting conditions.

Are ND Filters Worth It?

Absolutely! ND filters are a must-have for serious photographers and videographers who want better control over exposure and creative effects. Whether you’re capturing dreamy long exposures or achieving a natural motion blur in video, ND filters enhance your shots significantly.

For an efficient and easy-to-use system, check out the Freewell Magnetic Quick Swap System, which allows for rapid filter changes without threading.

Best ND Filter for a Sunny Day

On bright sunny days, using the right ND filter is crucial to avoid overexposure. Here are the best options:

• ND8 (3 stops) – Slightly reduces brightness for moderate sunlight

• ND16 (4 stops) – Ideal for general bright conditions

• ND32 (5 stops) – Best for very bright, harsh sunlight

A Variable ND Filter (VND) is also a great choice, allowing adjustable light reduction without changing filters. The Freewell V2 Hybrid VND & CPL offers both ND and CPL functions for maximum versatility.

The Neutral Density Rating chart is given below