ND filters come in various forms, strengths, and mounting styles, each designed to suit specific shooting needs and creative preferences. Here’s a breakdown of the main ND filter types:

Circular Screw-In & Magnetic ND Filters
These filters attach directly to the front of the lens via a screw thread or a magnetic adapter for quick installation. They are compact, convenient for everyday shooting, and available in multiple sizes to fit different lenses.

Square & Rectangular ND Filters
Typically used with filter holder systems, these filters offer flexibility for stacking multiple ND filters and combining with other accessories. While less portable, they are favored by professional landscape photographers for their versatility and ability to precisely control exposure.

Drop-In ND Filters
Designed for mirrorless or certain specialized camera systems, drop-in ND filters fit inside the camera body or lens mount. They are ideal for photographers seeking a minimalistic setup without adding bulk to the front of the lens.

Using ND filters is simpler than it may seem, but mastering them takes a bit of practice. Follow these steps to achieve precise exposure control and creative effects:

Mount Your Camera on a Tripod
ND filters are often used for long exposures. To avoid camera shake and ensure sharp images, always secure your camera on a stable tripod.

Frame Your Shot First
Compose your scene before attaching the ND filter. Darkened filters make it difficult to see through the viewfinder, so finalize your composition in advance.

Set Focus Before Installing the Filter
Lock in your focus manually or with autofocus before mounting the ND filter. After installation, the reduced light can interfere with accurate focusing.

Take a Test Shot Without the Filter
Capture a reference image to understand the baseline exposure. Record aperture, shutter speed, and ISO settings to guide your ND adjustments.

Choose the Appropriate ND Filter
Evaluate the lighting conditions and desired creative effect. Select the ND filter with the correct strength (e.g., ND8, ND64, ND1000) for your scene.

Install the ND Filter Correctly

• Screw-in or Magnetic ND: Twist onto the lens front.
• Square/Rectangular ND: Insert into the filter holder and slide to align.
  Ensure the filter is securely mounted and no light leaks occur.

Adjust Camera Settings for ND Compensation

• Switch to manual mode (M). For exposures longer than 30 seconds, use bulb mode.
• Calculate the new shutter speed:

Example: Original shutter speed = 1/30s, using ND64 (6 stops): 1/30 × 64 ≈ 2 seconds.

• Adjust aperture or ISO if needed to maintain desired exposure and depth of field.

Use a Remote Shutter or Timer
Trigger the shutter remotely to avoid any camera shake during long exposures.

Account for Changing Light Conditions
During sunrise or sunset, light levels change quickly:

• Sunrise: Consider reducing 1 stop.
• Sunset: Consider increasing 1 stop.

Alternatively, adjust aperture or ISO rather than further extending shutter speed.

This approach ensures you get sharp, balanced exposures while taking full advantage of ND filters for long-exposure or creative photography.

Selecting the perfect ND filter requires considering multiple factors to ensure it fits your shooting style and lighting conditions:

1. Filter Type
   Decide whether you need a variable ND filter for versatility across different scenarios, or a fixed-stop ND filter for optimal image quality and consistency.
2. Filter Shape
   Fixed ND filters come in round and square/rectangular formats. Each has its advantages: round filters are quick to mount and convenient for general use, while square filters paired with holders offer flexibility for stacking and positioning. Refer to our comparison guide if unsure which shape suits your lens system.
3. Filter Size
   Confirm the diameter of your lens. For photographers with multiple lenses, choose the filter that fits the largest lens. With circular ND filters, step-up rings allow compatibility with smaller lenses, making a single filter usable across your kit.
4. Filter Strength
   The required ND strength depends on ambient light and your intended creative effect. For most beginners, ND8 (3 stops) or ND64 (6 stops) provides a versatile solution suitable for a variety of lighting conditions.
5. Material & Price
   Once you’ve narrowed down size, shape, and strength, compare products. Optical glass filters with multi-layer or nano coatings deliver superior clarity and minimal color shift. Avoid low-cost resin filters if maximum image quality is your priority.

How many ND filters do I actually need?

The answer depends on your photography style and the lighting conditions you typically encounter. For beginners, owning two fixed-stop ND filters is often enough to cover most scenarios. You can also stack filters to achieve stronger light reduction. Variable ND filters offer added flexibility, allowing you to adjust the density without carrying multiple filters. However, for specialized techniques like ultra-long exposures, a high-strength ND filter such as ND1000 may be necessary.

How do I know which ND filter to use?

There’s no one-size-fits-all answer—it depends on your creative goal. Here’s a quick guideline:

• ND2 to ND8 (1–3 stops): Light reduction for slightly bright conditions or subtle motion blur.
• ND16 to ND64 (4–6 stops): Moderate reduction for daytime long exposures, like smoothing water surfaces or achieving shallow depth-of-field in bright sunlight.
• ND1000 and higher (10+ stops): Maximum light reduction for ultra-long exposures. Perfect for turning rushing water into silk or capturing dynamic cloud movement, even in strong daylight.
  

If unsure, start with a mid-range ND filter like ND8 or ND16—these work in a wide variety of conditions and give you room to experiment.

How do I choose the right ND filter size?

The filter size corresponds to your lens’s front diameter, typically marked in millimeters (e.g., 58mm, 72mm) on the lens barrel or cap. Always match the ND filter to this size. For photographers with multiple lenses of different diameters, buy the filter for the largest lens and use step-up rings to fit smaller lenses. This approach keeps your kit minimal while maximizing compatibility.