1. What is a Candlepower to Lumens Calculator?

Definition: This calculator converts candlepower (luminous intensity) to lumens (total luminous flux) for an isotropic light source.

Purpose: It helps lighting designers, engineers, and enthusiasts convert between these two important photometric measurements.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• Lumens — Total luminous flux (lm)
• Candlepower — Luminous intensity (cp)
• 4π — Conversion factor for isotropic source (steradians)

Explanation: Candlepower measures intensity in one direction, while lumens measure total light output in all directions.

3. Importance of Candlepower to Lumens Conversion

Details: Understanding this conversion helps in selecting proper lighting fixtures and comparing light sources accurately.

4. Using the Calculator

Tips: Simply enter the candlepower value (must be > 0) and the calculator will compute the equivalent lumens.

5. Frequently Asked Questions (FAQ)

Q1: What is candlepower?
A: Candlepower (cp) measures luminous intensity in a specific direction, expressed in candelas (cd).

Q2: What are lumens?
A: Lumens (lm) measure the total quantity of visible light emitted by a source in all directions.

Q3: Does this formula work for all light sources?
A: This assumes an isotropic (uniform in all directions) source. Directional sources require different calculations.

Q4: Why is 4π used in the formula?
A: 4π steradians represents the total solid angle around a sphere (360° in all directions).

Q5: How accurate is this conversion?
A: It's mathematically precise for isotropic sources, but real-world sources may vary based on their beam patterns.