Start with the everyday white or colour and the scenes the architecture needs, then choose the available engine.
RGB and RGBW describe channel arrangements, not complete specifications. RGB mixes red, green and blue channels. RGBW adds a white channel. The useful question is which arrangement can deliver the intended everyday appearance and occasion scenes in the selected outdoor fitting.
A white mix and a white channel are different
RGB channels can be mixed to produce a white-looking appearance. That mix is not automatically equivalent to a dedicated white LED channel in spectrum, colour rendition or output. A screen preview cannot establish those properties on a building.
RGBW provides a separate white channel alongside red, green and blue. Its actual white appearance and performance depend on the selected source and configuration. The letters alone do not establish colour temperature, colour rendering, usable output or the way white and colour channels can be combined.
Begin with the normal operating scene
For an entrance that is normally white and occasionally coloured, describe both requirements. Identify the materials, viewing positions, operating level and expected appearance of each scene. Ask for available evidence for the relevant white state and mixed-colour states, rather than comparing all configurations against one white-light number.
For an installation intended to remain one colour, also consider a dedicated single-colour source. A programmed fixed RGBW mix remains a multichannel operating state; it does not become a dedicated source.
Keep more-channel choices in their own comparison
CHROMA7 uses seven channels: red, green, blue, white, cyan, lime and amber. This offers additional mixing choices in compatible luminaires. Channel count alone does not prove that a particular scene is brighter, more accurate or more suitable for the material.
The separate RGBW versus RGBWCLA guide considers that next selection step. This RGB/RGBW explanation is about the role of the white channel, not a measured comparison of competing products.
Coordinate the driver and the intended operation
Confirm the exact channel map, supported interface, selected driver and operating mode. A controller description does not establish compatibility with every engine. If the everyday scene should run without a continuously connected controller, define a compatible preset and DMX arrangement.
Record how the agreed scene is set, who may change it, the DMX takeover condition and what should happen after signal loss or a restart. These behaviours belong to the documented configuration, not the RGBW label.
From channel choice to a luminaire
Choose the required engine alongside the optic, scale, mounting and environmental requirements. Modaluce's available options vary by fitting; this guide is not a statement that every model offers RGB, RGBW and CHROMA7.
Explore the outdoor colour selection and use Light Studio for supported visual studies. Bring the intended white and colour scenes to a configuration discussion.
Technical context
The CIE lighting vocabulary provides the underlying colour and photometric terminology. Product-specific spectral, output and control questions require the selected fitting's information. A visual comparison or channel label is not a performance test.
A selection record for the white-channel decision
Write the ordinary-night white requirement and occasion colours against the same material. Compare mixed RGB white, an available white channel and a dedicated white configuration according to their actual evidence, not a letter count.
In a hypothetical entrance brief, mark the required white appearance, colour scene, optic and control behaviour separately. Do not assume a white-looking screen mix establishes the needed spectrum, rendering or output.
Use the companion record to identify which Modaluce configuration is being reviewed and which scene-specific information remains outstanding. The completed example is a review method, not a measured comparison.
Use the white and colour selection Excel workbook for the editable record, instructions, field guidance and fictional worked examples. The PDF companion provides a printable guide. All worked examples are fictional and are not project records, product-test results or accepted specifications.
