Spectrum Degrees (°S)

Spectrum Degrees (°S) is a new colour measurement system created as part of Universal Colour Theory. It defines hue using the physical structure of light itself, not digital codes or pigment mixes

Invented by Funky Love Bunny

Visible Spectrum

Each Spectrum Degree (°S) corresponds directly to 1 nanometre (nm) of the physical wavelength of a light wave in the visible spectrum. 

The scale spans from 380 nm to 739 nm, matching the full range of typical human vision, & maps this onto a clean 360° circular system or a band of 360 stripes of hue degrees. Spectrum Degrees exist as single wavelengths of light, not mixed tones, tints, or shades.

Structure of the Scale

The visible spectrum covers a 360 nm range of wavelengths: 

from 380 nm (violet) to 739 nm (red)

That range is divided into 360 equal steps

Each 1°S = 1 nm

This system allows you to assign a simple, universal value to any spectral hue:

1°S = 380 nm → Deep violet

Start of the human visible light spectrum

180°S = 560 nm → Yellow-green

The most sensitive peak point of human vision (560 nm) is cleanly & neatly defined as 180°S, the midpoint of visible hue as well as a circle.

360°S = 739 nm → Deep Tempa (see below)

End of the human visible light spectrum 

Conversion Formulas

To convert from Spectrum Degrees (°S) to wavelength (λ):

λ = 379 + °S

Example: Spectrum Degrees = 136°S → λ = 379 + 136°S = 515 nm

To convert from wavelength (λ) to Spectrum Degrees (°S):

°S = λ − 379

Example: Wavelength = 510 nm → °S = 510 − 379 = 131°S

A True Hue Compass

Spectrum Degrees are not an opinion, code, or metaphor. They are a direct scale of real measurable light wavelengths, a circular map of pure hue. Not all colours can be placed on this scale. But every true visible hue can

Pure Hues Only

Spectrum Degrees measure pure spectral hues, the colours that exist as single wavelengths of light.

This scale does not apply to mixed colours, such as:

Pinks, browns, or greys, Tints (hue + white), Shades (hue + black) & Non-spectral blends like magenta or turquoise

Those colours are combinations of multiple wavelengths.

Spectrum Degrees instead give us a way to measure the pure hue component within those blends that are the structural backbone of all colour.

Tempa (T)

Tempa is a newly coined term by Funky Love Bunny to describe the Terminal hue at the warm end of the visible spectrum — the perceptual point where red transitions into black. While the cool end of the spectrum has a well-established term, violet, marking the boundary between black & blue, there is no equivalent term for the infrared-facing end, where red fades into darkness. This omission creates an imbalance in how we refer to spectral limits.

The name Tempa was selected to fill this gap. It evokes the visual characteristics of materials such as lava, magma, or molten metal as they cool, the red fading toward black & without relying on primary or secondary colour initials. The letter T was chosen specifically to avoid conflict with other hue identifiers (e.g. R, G, B, Y, M, C, L etc..).

Alternative terms like Ember were considered, but rejected due to overlap with E, which in Phen Theory is reserved for the origin point known as "Emergence". Also Lava but L might cuase confusing with the peak Lime like hue at 180ºS & Magma with Magentas M etc..

 Tempa also alludes to Temperature, appropriate for this end of the spectrum, which borders the infrared range. We even "see red" when our Temper gets out of control. Additionally, it draws subtle inspiration from terms like Tempering (in metallurgy) & Tempera (in pigment fixing), reinforcing the idea of constrained, internalised heat.

Tempa is not black, but it sits at the perceptual threshold just before red becomes unseeable . It's the concentrated hue at the far limit of visibility.

Real World Use Case Examples

Lighting control: Adjust LED strips to 215°S for rich warm ambers, or 150°S for balanced greens

Photography & colour grading: Reference light temperature in physical terms. “This shot leans too far toward 115°S, shift it warmer by 10°”

Stage & event design: Match light accents precisely across setups. “The uplights are set to 155°S, shift all side lighting to within 5° of that”

Home lighting apps GUI for multicolour LED lighting: Circular user interface with spectrum degrees labled as they rotate so that the user is able to remeber their favourite hues by a specific Spectrum degree - "Set the pool lights to 75ºS for the party tonight"