Night Shift color temperature measurements in nanometers on iPhone

Color temperature is measured in degrees Kelvin. I have a Minolta Color meter and can provide rough estimates of color temperature. Do you have formula to convert degrees Kelvin to nanometer?

This is from Google AI,

To convert degrees Kelvin (temperature) to nanometers (wavelength), you'll use Wien's Displacement Law. This law establishes a relationship between the temperature of a black body and the wavelength at which it emits the most radiation.

Here's how you can do it:

1. Wien's Displacement Law Formula:

λ_max = b / T

Where:

• λ_max is the peak wavelength in meters (which you'll convert to nanometers).
• b is Wien's displacement constant, approximately 2.898 × 10^-3 m·K.
• T is the temperature in Kelvin.

1. 1. Calculate the Peak Wavelength (λ_max):

• • Substitute the temperature (T) in Kelvin into the formula.
  • Calculate the peak wavelength (λ_max) in meters.

1. 2. Convert Meters to Nanometers:

• • Since 1 meter = 10⁹ nanometers, multiply the wavelength in meters by 10⁹ to get the wavelength in nanometers.

Example:

Let's say you have a temperature of 6000 K.

1. Calculate λ_max in meters:

λ_max = (2.898 × 10^-3 m·K) / 6000 K

λ_max ≈ 4.83 × 10^-7 m

1. Convert to nanometers:

λ_max ≈ (4.83 × 10^-7 m) * (10⁹ nm/m)

λ_max ≈ 483 nm

Therefore, a blackbody at 6000 K would have its peak emission at around 483 nanometers (which is in the blue-green part of the visible spectrum).

In essence, higher temperatures correspond to shorter wavelengths (bluer light), while lower temperatures correspond to longer wavelengths (redder light).