Theater Lighting Intensity Calculator
Calculate optimal lighting intensity for a stage performance based on stage size, performance type, audience distance, and ambient light.
Formulas Used
The Lighting Intensity Score is calculated using a weighted formula assessing stage size, performance type, audience distance, and ambient light.
- Stage-Performance Alignment Score:
\\[ S_{\text{align}} = \frac{S + P}{2} \\]
Where \\( S \\) is stage size and \\( P \\) is performance type. Averages stage size and performance type to reflect lighting needs for scale and dynamics.
- Distance-Ambient Adjustment Score:
\\[ D_{\text{adj}} = D + \frac{A}{2} \\]
Where \\( D \\) is audience distance and \\( A \\) is ambient light. Increases lighting needs based on distance and ambient interference.
- Raw Lighting Score:
\\[ L_{\text{raw}} = w_1 S_{\text{align}} + w_2 D_{\text{adj}} \\]
Where:
- \\( S_{\text{align}} \\): Stage-performance alignment score
- \\( D_{\text{adj}} \\): Distance-ambient adjustment score
- \\( w_1 = 10 \\): Weight for alignment
- \\( w_2 = 5 \\): Weight for adjustment
- Lighting Intensity Score:
\\[ \text{LIS} = \max\left(0, \min\left(100, \frac{L_{\text{raw}}}{100} \cdot 100\right)\right) \\]
Normalizes the raw score to 0–100. Ratings: Low (0–25), Moderate (25–50), High (50–75), Very High (75–100).
- Intensity Requirement Factor:
\\[ R_{\text{req}} = \frac{(S + D) \cdot A}{P} \\]
Estimates relative lighting demand based on stage size (\\( S \\)), audience distance (\\( D \\)), and ambient light (\\( A \\)) relative to performance type (\\( P \\)). Higher values indicate greater intensity needs.
Example Calculations
Example 1: Small Intimate Play
Inputs: Stage Size = 1, Performance Type = 1, Audience Distance = 1, Ambient Light = 1
Calculations:
- Stage-Performance Alignment Score: \\[ \frac{1 + 1}{2} = 1 \\]
- Distance-Ambient Adjustment Score: \\[ 1 + \frac{1}{2} = 1.5 \\]
- Raw Lighting Score: \\[ 10 \cdot 1 + 5 \cdot 1.5 = 10 + 7.5 = 17.5 \\]
- Lighting Intensity Score: \\[ \frac{17.5}{100} \cdot 100 = 17.5 \\]
- Intensity Requirement Factor: \\[ \frac{(1 + 1) \cdot 1}{1} = 2 \\]
- Rating: Low (0–25)
Result: Lighting Intensity Score: 17.5 (Low), Intensity Requirement: Minimal
Example 2: Large Musical Outdoors
Inputs: Stage Size = 5, Performance Type = 5, Audience Distance = 5, Ambient Light = 4
Calculations:
- Stage-Performance Alignment Score: \\[ \frac{5 + 5}{2} = 5 \\]
- Distance-Ambient Adjustment Score: \\[ 5 + \frac{4}{2} = 7 \\]
- Raw Lighting Score: \\[ 10 \cdot 5 + 5 \cdot 7 = 50 + 35 = 85 \\]
- Lighting Intensity Score: \\[ \frac{85}{100} \cdot 100 = 85 \\]
- Intensity Requirement Factor: \\[ \frac{(5 + 5) \cdot 4}{5} = 8 \\]
- Rating: Very High (75–100)
Result: Lighting Intensity Score: 85 (Very High), Intensity Requirement: Significant
Example 3: Medium Drama
Inputs: Stage Size = 3, Performance Type = 3, Audience Distance = 3, Ambient Light = 2
Calculations:
- Stage-Performance Alignment Score: \\[ \frac{3 + 3}{2} = 3 \\]
- Distance-Ambient Adjustment Score: \\[ 3 + \frac{2}{2} = 4 \\]
- Raw Lighting Score: \\[ 10 \cdot 3 + 5 \cdot 4 = 30 + 20 = 50 \\]
- Lighting Intensity Score: \\[ \frac{50}{100} \cdot 100 = 50 \\]
- Intensity Requirement Factor: \\[ \frac{(3 + 3) \cdot 2}{3} = 4 \\]
- Rating: Moderate (25–50)
Result: Lighting Intensity Score: 50 (Moderate), Intensity Requirement: Average
How to Use the Calculator
Follow these steps to calculate optimal lighting intensity for a stage performance:
- Enter Stage Size: Rate the stage area (1–5, 1 = small ~50 m², 5 = large ~500 m²).
- Enter Performance Type: Rate the performance’s dynamic nature (1–5, 1 = intimate like monologue, 5 = dynamic like musical).
- Enter Audience Distance: Rate the distance to the audience (1–5, 1 = close ~5 m, 5 = far ~50 m).
- Enter Ambient Light: Rate the venue’s ambient light (1–5, 1 = low/dark, 5 = high/outdoor daylight).
- Calculate: Click “Calculate” in the keypad to see the result.
- Interpret Result: The result shows a 0–100 score with a rating (Low: 0–25, Moderate: 25–50, High: 50–75, Very High: 75–100) and intensity requirement (minimal, average, significant). If you see “Please fill in all fields,” ensure all inputs are valid.
- Share or Embed: Use the share buttons to post results on social media, copy the result, or get an embed code.
Note: This is a simplified model. Actual lighting depends on specific fixtures (e.g., LED, tungsten), color temperature, beam angles, and artistic direction. Consult a lighting designer or use software like Vectorworks for precise plans.