Long Exposure Photography Techniques — Complete Guide

Long exposure photography extends the shutter speed beyond what freezes motion — typically from half a second to several minutes. During that time, anything that moves is recorded as blur, streaks, or silky smooth abstraction, while anything still remains sharp. The technique transforms waterfalls into silk ribbons, clouds into painted brushstrokes, traffic into rivers of light, and ocean waves into mist. This guide covers the full technique: equipment, settings, subjects, and creative applications for wedding and portrait work.

Essential Equipment

Tripod

Non-negotiable for long exposures. Any camera movement during a multi-second exposure ruins the image. Use a sturdy tripod, extend the legs fully, hang a weight from the centre column hook in wind, and do not extend the centre column (it introduces vibration). On soft ground, press the leg tips in firmly.

Remote Trigger

Pressing the shutter button by hand introduces vibration. Use a cable release, wireless remote, or the camera's built-in 2-second timer to trigger the shutter without touching the camera.

ND Filters

Neutral Density filters reduce light entering the lens, enabling slow shutter speeds in bright conditions. Without an ND filter, a correctly exposed image at ISO 100, f/11 in daylight is around 1/125s — far too fast for long exposure effects. An ND filter extends this:

• ND8 (3 stops): 1/125s becomes 1/15s — enough for subtle water blur.
• ND64 (6 stops): 1/125s becomes 0.5s — smooth water, slight cloud movement.
• ND1000 (10 stops): 1/125s becomes 8 seconds — silky water, streaked clouds.
• ND32000 (15 stops): 1/125s becomes 4 minutes — clouds become fog, water becomes glass, moving people disappear entirely.

Camera Settings

• Mode: Manual or Bulb (for exposures longer than 30 seconds).
• ISO: lowest available (100 or 50). This maximises image quality and extends exposure time.
• Aperture: f/8 to f/11 for sharpness across the frame. Avoid f/22 — diffraction softens the image. If more light reduction is needed, use a stronger ND filter, not a smaller aperture.
• Focus: autofocus before attaching the ND filter (dark filters prevent autofocus). Then switch to manual focus so the focus doesn't hunt during exposure.
• Mirror lock-up: on DSLRs, enabling mirror lock-up eliminates vibration from the mirror flipping. Mirrorless cameras don't have this issue.
• Long exposure noise reduction: available on most cameras. It takes a second exposure of equal length with the shutter closed (a "dark frame") and subtracts the sensor noise. Doubles the capture time but reduces hot pixels and noise in very long exposures.

Subjects for Long Exposure

Water — Rivers, Waterfalls, Oceans

The most popular long exposure subject. Moving water recorded over 1-30 seconds transforms into smooth, silky ribbons or ethereal mist. The longer the exposure, the smoother the water:

• 1/4s to 1s: water shows clear motion with some texture — individual waves and ripples still readable.
• 2-8s: water becomes smooth and silky but retains flowing shapes — the classic waterfall look.
• 30s+: water becomes a flat, featureless mirror — extremely calm, minimalist, abstract.

Clouds

Moving clouds recorded over 30 seconds to several minutes create dramatic streaks across the sky. Faster-moving clouds produce more dramatic streaks. On a windy day, a 2-minute exposure transforms scattered cumulus clouds into long, flowing brushstrokes racing across the frame.

Traffic Light Trails

Vehicle headlights and tail lights recorded at 10-30 seconds create rivers of white and red light flowing through cityscapes. Shoot from bridges, overpasses, or elevated positions for the most dramatic perspectives.

Star Trails

The ultimate long exposure. Exposures of 30 minutes to several hours record the apparent rotation of stars around the celestial pole, creating circular arc trails. Alternatively, stack multiple 30-second exposures to create the same effect without a single extremely long exposure.

Long Exposure in Wedding Photography

Venue by Water

Wedding venues near rivers, lakes, or the coast offer long exposure opportunities. A 10-second exposure of the venue reflected in glass-smooth water produces a serene, timeless establishing shot impossible to achieve at normal shutter speeds.

Couple by the Sea

The couple standing still on rocks while ocean waves turn to mist around their feet. A 2-5 second exposure with the couple perfectly still records them sharply while the water flows like silk. They'll need to hold completely still — brief the couple beforehand.

Evening Venue with Moving Guests

A long exposure of the venue at dusk — guests moving through the scene become ghostly blurs while the building and lit windows remain sharp. The contrast between the solid architecture and the ephemeral guest movement tells a story of celebration and transience.

Sparkler Exits

Sparklers are moving light sources — perfect for long exposure. A 1-2 second exposure while guests wave sparklers creates arcs and streaks of light framing the couple. Combined with a rear-curtain flash to freeze the couple, this produces the classic sparkler exit shot.

Calculating Long Exposure Times

With an ND filter, the maths is simple. Take your base exposure without the filter, then multiply by the filter factor:

• Base exposure: 1/125s × ND1000 (10 stops) = 8 seconds.
• Base exposure: 1/60s × ND1000 = 16 seconds.
• Base exposure: 1/125s × ND32000 (15 stops) = 4 minutes 16 seconds.

Long exposure calculator apps (like PhotoPills or NDTimer) do this automatically — input the ND filter strength and the base exposure, and the app shows the required shutter speed.

Post-Processing Long Exposures

• Colour cast correction: some ND filters introduce a colour shift (typically warm or purple). Correct in white balance or with a hue shift.
• Contrast boost: long exposures can look flat due to the blending of tones over time. Add contrast to restore punch.
• Vignetting correction: thick ND filters can cause mechanical vignetting — dark corners. Correct with lens profile corrections or the vignette slider.
• Hot pixel removal: very long exposures produce hot pixels (bright specks caused by sensor heat). Long exposure noise reduction eliminates most; remaining spots can be removed with the spot healing tool.