Visual feedback — like on camera screens — is convenient. But metering light links light output to your camera's aperture.
Metering allows you to match your strobe's power to a specific aperture — or set your aperture based on the light's output — with technical precision rather than guesswork.
Step 01: Reading the Scale — Values Explained
Our meter displays Lux, Foot-candles, Exposure Value, and f-stop.
While Lux and FC measure raw physical intensity — matching real-world hardware specs and for cinematographers — the EV serves as a standardized value for the light's actual output.
In photography, however, the f-stop is your primary currency. It translates that raw energy into an actionable camera setting. To prioritize the creative workflow, I'll refer to f-stops exclusively for the rest of this article.
Step 02: Light Metering — How To
Setting up takes just a few clicks. Follow these steps to determine the correct f-stop for any light in your scene.
- 1 + 2: Open the Equipment tab and select the Light Meter.
- 3: Drag it onto the set and position it near your subject. Face the sensor toward the light source you want to measure (e.g., the Key Light).
- 4: In the left-hand panel, ensure the meter's settings match your camera's ISO and Shutter Speed.
- 5 + 6: With the meter selected, click the Eye Icon on the light you want to measure. The meter will automatically align for a precise, real-time reading.
- 7: Adjust your camera's aperture or the light's power until you reach your target exposure.
Step 03: Light Ratios — Defining the Mood
The real control and creative work starts when balancing multiple light sources. By measuring the difference in f-stops or EV between your sources (aka Light Ratios), you move beyond technical guesswork to precisely define the mood, look, and contrast of your image.
How to read the ratio logic in the illustration:
- Base Aperture: Your primary exposure setting for the Key light (here it's f/5.6).
- The Ratio: Represents the intensity relationship. A 4:1 ratio means your second light source (the Fill) is four times as weak as the primary light.
- The Resulting Value: Since we are using f-stops as our currency, a 4:1 difference equals exactly two full stops. To achieve this ratio, your fill light must meter at f/2.8.
Step 04: Metering Light Ratios in Concepts
This is where the technical values — f-stops, EVs and ratios — translate into a visual signature. By choosing a specific ratio, you determine the image's emotional weight.
- A — 1:1 (0 Stops), Beauty Look: Flat, soft, and virtually shadowless. The go-to where the goal is perfect, even skin (f/5.6 Key / f/5.6 Fill).
- B — 3:1 (1.5 Stops), Soft Dimension: A noticeable but gentle drop-off. Provides enough depth to shape the face without feeling moody — ideal for classic, flattering portraiture (f/5.6 Key / f/3.5 Fill).
- C — 4:1 (2 Stops), Dramatic Casual: High contrast with defined shadows. Builds a power look that works well for character-driven portraits or athletic shots (f/8 Key / f/4 Fill).
- D — 8:1 (3 Stops), Fine Art / Noir: Very high contrast. Shadows fall into deep blacks, making highlights pop for a classic B&W or Chiaroscuro cinematic mood (f/8 Key / f/2.8 Fill).
Conclusion
Investing a few minutes to learn the light meter in set.a.light 3D V3 pays off immediately on set. It turns guesswork into a repeatable system, giving you the technical foundation to build your vision with total confidence — whether you're aiming for a soft beauty glow or a dramatic fine-art portrait.
Have fun trying it out,
Dan from elixxier
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