K · CCT
Colour temperature: 2700 K appears warm; 6500 K cool. It does not measure output or colour fidelity.
LIGHT LAB
Light changes what we see.
One light. Four backgrounds. Explore how colour, temperature and direction transform the way we perceive an object.
97 PBR textures from Poly Haven and ambientCG: photographs, scans and procedural materials. Loaded on selection.
Illustrative visual comparison, not a photometric calculation or spectral reproduction. All backgrounds share a dim, neutral ambient light.
3D models: Rico Cilliers and Tina / Poly Haven · CC0THE LIGHT LAB · 02
Light quality
Generic CIE reference spectra, not commercial products. TCS samples represent colours, not material photographs. CRI/R9 and TM-30-18 are calculated from the spectrum; intensity and optics do not change these indices. White-adapted sRGB preview, limited by your display.
Select a sample to enlarge it. Each pair shows the same surface under sources A and B.
Times of day illustrate spectra, not measurements at a particular time or location. Natural light varies with atmosphere and surroundings. CRI uses a reference of similar colour temperature; CRI 100 does not mean white or cool light.
SIM-CRI 60–99 are synthetic teaching spectra: they mix CIE LED-RGB1 with an ideal 2840 K reference and calculate the resulting CRI. They do not represent commercial products or measurements of a specific LED.
Each sample compares A and B without exaggerating the difference. ΔE00 is calculated before display-gamut clipping. Zero means equal; larger values mean greater differences. ΔE00 is calculated after adaptation to D65 and stays unchanged when the display white balance changes.
Application: Colour chart
Application selects colour samples relevant to the exercise; it does not load photographs or change the source spectra.
TCS01 · Greyish red · TCS02 · Greyish yellow · TCS03 · Yellow green · TCS04 · Soft green · TCS05 · Blue green · TCS06 · Light blue · TCS07 · Light violet · TCS08 · Reddish purple · TCS09 · Strong red · TCS10 · Strong yellow · TCS11 · Strong green · TCS12 · Strong blue · TCS13 · Skin pink · TCS14 · Olive green
Select an A/B tile to enlarge that sample. The chart includes 14 colours; applications show a selection of six.
Data and method
CIE 2018 · DOI 10.25039/CIE.DS.vgssnyfg · CC BY-SA 4.0. Colour Science 0.4.7 · CRI CIE 1995 / ANSI/IES TM-30-18 · TCS 01–14 · Bradford → sRGB.
CIE · Reference spectrum · Data and method · JSON · CC BY-SA 4.0Understanding light
CRI · Ra
Average of eight low-saturation colours, up to 100. Poor reds can be hidden; check R9 and TM-30.
R9
Saturated red: relevant to skin, food and wood. It can be negative even with a high Ra.
TM-30 · Rf
Fidelity across 99 samples, up to 100. Compare similar colour temperatures; it is not interchangeable with CRI.
TM-30 · Rg
Gamut area relative to reference: 100 equal, above usually more average saturation, below less. Higher is not automatically better.
SPD · nm
Energy distribution by wavelength. Lights with equal kelvin can render colours differently. Neither CRI nor a screen replaces a physical sample.
Each sample compares A and B without exaggerating the difference. ΔE00 is calculated before display-gamut clipping. Zero means equal; larger values mean greater differences.
Reference, not LED: A · D50 · D65 · 3000 K.
High-fidelity LEDs
Orluna Origin Natural · CRI 98 · R9 99
Waveform ABSOLUTE SERIES · CRI 99 · 6500 K
Energy distribution by wavelength. Lights with equal kelvin can render colours differently. Neither CRI nor a screen replaces a physical sample.
Wavelength ↔ Frequency · Photon energy
nm means nanometres. Hues are sRGB approximations; a screen cannot reproduce monochromatic light or its true brightness.
ν = c / λ · E = hν · c = 299 792 458 m/s
CIE 1931 · 2° · XYZ → sRGBCRI Ra averages eight colour samples; R9 assesses saturated red. TM-30 Rf describes average fidelity and Rg the gamut area relative to the reference: 100 means equal area, not maximum quality. Profiles have different colour temperatures; compare their kelvin values too.
| Reference spectrum | K | CRI Ra | R9 | Rf | Rg |
|---|---|---|---|---|---|
| LED-B1 | 2733 | 81.8 | 12.6 | 84.1 | 96.1 |
| LED-B2 | 2998 | 82.8 | 17.6 | 84.3 | 96.6 |
| LED-B3 | 4102 | 84.8 | 23.8 | 85.3 | 97.9 |
| LED-B4 | 5109 | 76.8 | -1.6 | 76.9 | 95.5 |
| LED-B5 | 6598 | 80.2 | 6.9 | 79.5 | 94.1 |
| LED-BH1 | 2851 | 91.8 | 73.5 | 85.2 | 106.8 |
| LED-RGB1 | 2840 | 57.1 | -34.2 | 71 | 107 |
| LED-V1 | 2724 | 95.3 | 97.9 | 87.3 | 101.9 |
| LED-V2 | 4069 | 95.7 | 95 | 94.1 | 99.3 |
| REF-A | 2856 | 100 | 100 | 100 | 100 |
| REF-D50 | 5002 | 100 | 100 | 100 | 100 |
| REF-D65 | 6503 | 100 | 100 | 100 | 100 |
| Ideal CRI 100 reference | 3000 | 100 | 100 | 100 | 100 |
| Warm sunrise / sunset · ideal model | 2200 | 100 | 100 | 100 | 100 |
| Warm morning · daylight model | 4001 | 97.9 | 91.3 | 96.5 | 99.1 |
| Midday · daylight model | 5502 | 100 | 99.9 | 100 | 100 |
| Overcast sky · daylight model | 7505 | 100 | 100 | 100 | 100 |
| Shade / blue sky · daylight model | 10005 | 100 | 100 | 100 | 100 |
| SIM-CRI60 | 2840 | 60 | -25.8 | 72.9 | 106.9 |
| SIM-CRI70 | 2840 | 70 | 4 | 79.4 | 106 |
| SIM-CRI80 | 2840 | 80 | 34.8 | 86.1 | 104.5 |
| SIM-CRI90 | 2840 | 90 | 66.8 | 93 | 102.5 |
| SIM-CRI95 | 2840 | 95 | 83.2 | 96.5 | 101.3 |
| SIM-CRI98 | 2840 | 98 | 93.2 | 98.6 | 100.6 |
| SIM-CRI99 | 2840 | 99 | 96.6 | 99.3 | 100.3 |
THE LIGHT LAB · 03
Dynamic pixel lighting
Visual demonstration of addressable LEDs: each pixel has its own colour. Room illumination is approximated in groups. Lutron compatibility depends on the controller and the specific integration.
Pixel count changes colour resolution at approximately constant total power. Diffusion blends light without changing dimensions. Palette stops do not limit the available colours.
Data and method · SPI / RGBW · ENTTEC
THE LIGHT LAB · 04
Design tools
Indicative calculations under the stated assumptions. They do not replace a photometric design or manufacturer electrical selection. There is no universal lumens-to-nits conversion.
Beam and distance
Calculate beam diameter on a plane and centre illuminance at a given distance.
With a FWHM angle, the diameter is the 50% intensity contour, not the edge of the light. Circular beams only.
Result
Beam diameter: 192.9 cm
Illuminance: 142.4 lx
D = 2d tan(θ/2) · E = I/dₘ² (0°)Plane perpendicular to the beam axis and a point source in the far field. Candela must come from photometric data; it is not derived from colour or simulator percentage.
Data and method · Konica MinoltaLuminaire estimate
Estimate the number of luminaires needed for an average illuminance over an area.
Result
13Estimated quantity
N = ⌈A × E / (Φ × UF × MF)⌉Lumen method for average illuminance. Enter project-specific UF/MF factors. It does not calculate uniformity, glare or point-by-point distribution.
Data and method · Konica MinoltaLED tape and power
Calculate LED strip load and supply capacity with headroom.
Strip length multiplied by W/m gives its load. Headroom reserves supply capacity; check voltage, voltage drop and manufacturer limits.
Result
Power: 60 W
Current: 2.5 A
Power + Power margin: 72 W
P = m × W/m · I = P/VContinuous nominal power. The margin is added to the load, not to supply capacity. Check voltage drop, feed points and manufacturer limits.
Data and method · Konica MinoltaUnits and surfaces
Convert units and estimate the brightness of a matt surface. Calculations are independent: length does not resize or change the 3D scene.
Lux (lx) is light received per m²; lumen (lm) is emitted flux. cd/m² or nit measures luminance; lm/W measures luminous efficacy.
Result
300 lx = 27.87 fc
Luminance · Lambert: 47.75 cd/m² = 47.75 nit
L = Eρ/πLuminous efficacy: 100 lm/W
5 m = 16.4 ft = 196.85 in
L = Eρ/π assumes a uniformly illuminated matte Lambertian surface. It does not describe emissive screens, glass or specular surfaces.
Data and method · Konica Minolta