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RGB composite

Render a multi-band raster source — typically a Cloud Optimized GeoTIFF — as a true-colour or false-colour composite by mapping three bands to the Red, Green, and Blue channels.

When to use

  • Sentinel-2 / Landsat / Planet / aerial imagery where you want a natural-looking picture (e.g. bands 4-3-2 for Sentinel-2 true colour)
  • False-colour analysis (e.g. NIR-Red-Green for vegetation)
  • Hyperspectral cubes where you want to inspect a specific three-band slice

For single-band products use a Colormap instead.

How the configuration is stored

RGB composites are driven per data source, not at the layer level. Each item in a layer's data array gets:

  • convertToRGB: true
  • bands: [r, g, b] — exactly three band indices (1-based), in R/G/B order

This means a single layer can hold multiple COGs (e.g. one per scene) and the same band selection applies uniformly. The legacy layer-level rgbComposites property has been removed from the schema — do not add it manually.

Configuring an RGB composite

  1. Open the layer card and expand Data Visualisation
  2. Click the + next to RGB Composite
  3. The editor lists every band detected in the source (from COG metadata)
  4. Select exactly three bands — they will be assigned R, G, B in selection order
  5. Reorder by clicking the R / G / B chips on each selected band
  6. Save — the badge in the layer card now shows coloured R: n, G: n, B: n chips

Advanced settings (per-channel min/max)

Once exactly three bands are selected, an Advanced Settings ››› button appears beneath the Selected Bands list. Opening it:

  • Hides the band-selection columns to give the channel editor more room
  • Shows a histogram and min / max input for each of R, G, B
  • Persists the values as an OpenLayers-compatible style block on each data source item

The viewer only loads the three bands you requested, so the persisted style always references them as rBand: 1, gBand: 2, bBand: 3 regardless of the original band numbers — this remapping is automatic.

When to tune min/max

Imagery often has an overall brightness range that doesn't match its true value range (e.g. 16-bit data with most values in a narrow window). Setting tighter min/max values per channel dramatically improves contrast without altering the underlying data.

Bulk behaviour

Deleting the RGB Composite bulk-removes convertToRGB and bands from every data source under the layer. Use this when switching to a categorical or colormap rendering.