DEMO — fictional range. Local brief only, NOT SENT. No personal data is collected or transmitted.
SOURCE
The fitting is a housing. The source is the light.
A luminaire is judged by its source, and the source is a set of four numbers that are independent of the housing around it.
- Colour temperature
- How warm or neutral the light reads, in kelvin
- Colour rendering
- How faithfully materials read, as a CRI or a TM-30 figure
- Output
- Lumens delivered, at the fitting rather than at the emitter
- Beam angle
- The shape of the light, which is the number a layout is drawn from
- Colour consistency
- How closely two fittings of the same type match, which is a binning decision
- Life and depreciation
- How long it lasts, and how much output it loses before then
Illustrative source record
| Property | Typical range | What it decides |
|---|---|---|
| Colour temperature | Example · 2700 to 4000 K | The warmth of the room, and whether fittings match |
| Colour rendering | Example · CRI 80 to 95 | How timber, fabric and food read |
| Output | Example · 500 to 1200 lm | The number of fittings, at the beam chosen |
| Beam angle | Example · 15 to 60 degrees | The layout, and how many fittings cover a surface |
Why colour consistency is a separate number.
Because two fittings of the same nominal temperature can differ visibly. A scheme with twenty fittings is judged on the worst pair in the room, which is a binning decision rather than a specification.
The question worth asking instead.
What the delivered output is at the fitting, at the beam angle chosen, and how closely fittings of the same order match. A supplier who can answer that has measured the product rather than the emitter.