Color Temperature Calculator

Wien's Law Formula:

\[ CCT = \frac{2.897 \times 10^6}{\lambda} \]

Color Temperature (CCT):

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1. What is Color Temperature?

Color temperature is a characteristic of visible light that describes the color of light emitted by an idealized black-body radiator. It is measured in kelvins (K) and indicates whether light appears warm (yellow/red) or cool (blue).

2. How Does the Calculator Work?

The calculator uses Wien's displacement law:

\[ CCT = \frac{2.897 \times 10^6}{\lambda} \]

Where:

\( CCT \) — Color temperature in kelvins (K)
\( \lambda \) — Wavelength in nanometers (nm)
\( 2.897 \times 10^6 \) — Wien's displacement constant

Explanation: Wien's law states that the wavelength at which the emission of a black body peaks is inversely proportional to its temperature.

3. Importance of Color Temperature Calculation

Details: Color temperature is crucial in photography, lighting design, display technology, and astronomy. It helps determine the quality and characteristics of light sources and their applications in various fields.

4. Using the Calculator

Tips: Enter the wavelength in nanometers (nm). The value must be greater than 0. Common visible light wavelengths range from 380 nm (violet) to 750 nm (red).

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between wavelength and color temperature?
A: Shorter wavelengths correspond to higher color temperatures (bluer light), while longer wavelengths correspond to lower color temperatures (redder light).

Q2: What are typical color temperature values?
A: Candlelight: ~1800K, Incandescent bulbs: 2700-3000K, Daylight: 5000-6500K, Overcast sky: 6500-8000K.

Q3: Is this calculation accurate for all light sources?
A: This calculation is most accurate for black-body radiators. Real light sources may have different spectral distributions.

Q4: Can I use this for LED lighting?
A: While LEDs approximate black-body radiation, their actual color temperature may vary due to phosphor coatings and manufacturing processes.

Q5: What is the visible spectrum range?
A: The human eye typically perceives light between 380 nm (violet) and 750 nm (red), corresponding to color temperatures from approximately 7600K to 3900K.