Old Film: Dust Video Filter

The Old Film: Dust filter simulates dust particles and fine debris commonly visible in analog film projection.
In physical film formats, dust, lint, and hair could settle on the film surface or inside the projector gate, briefly appearing as spots or short streaks as the film passed through the light path.

This filter recreates those transient artifacts for creative and historical effect, not restoration.

Parameters

Size (1 - 100)

Controls the apparent size of dust particles.

• Lower values
  Small, fine dust specks and hair-like artifacts

• Higher values
  Larger, more noticeable debris

This parameter affects the visual scale of each particle.

Note:

High values can quickly become unrealistic.

Amount (1 - 400)

Controls the number of dust particles visible over time.

• Lower values
  Sparse, occasional dust artifacts

• Higher values
  Dense dust activity, with many particles appearing

This parameter controls the effective footprint of dust particles.
Higher values can cause particles to overlap and cluster, increasing the perceived density of dust.

Usage notes

• The effect is temporal: dust particles appear, move, and disappear over time.
• Evaluating the filter on a single frame is misleading.
• For accurate preview, play the video to observe particle motion and frequency.

Subtle settings usually produce the most realistic results.

Visual characteristics

Typical effects include:

• Small specks briefly appearing in the frame
• Short-lived artifacts that move or flicker
• Random distribution over time
• Greater realism at lower Size and Amount values

The artifacts are not fixed to the image content and change from frame to frame.

Dust vs Scratches

Although both filters simulate film damage, they represent different physical causes:

• Old Film: Dust
  Simulates loose particles (dust, lint, hair) that intermittently block or scatter light during projection.
  Artifacts are small, transient, and randomly distributed.

• Old Film: Scratches
  Simulates permanent damage to the film surface itself.
  Artifacts are elongated, usually vertical, and persistent across frames.

Using both together can produce a more complete aged-film effect.

Recommended use cases

• Vintage or archival-style visuals
• Simulating projected film rather than film stock alone
• Subtle degradation effects
• Combining with other Old Film filters (Scratches, Projector, Grain,…)

Limitations

• Parameters are not keyframeable
• Procedural effect, not derived from image content
• High values may obscure details
• Intended for stylized use