Mastering the use of a Sekonic light meter is the single most effective step you can take to consistently achieve perfect exposure in your photography. Whether you are working with film or digital, these handheld devices translate the complex language of light into a concrete numerical reading that removes guesswork from the equation. Instead of relying on the often-deceptive preview of your camera or the harsh judgment of a histogram after the shot, you gather the light data before you even press the shutter.
Understanding Incident vs. Reflected Light
The foundation of using a Sekonic meter effectively lies in understanding the two primary modes of measurement. Incident metering involves placing the sensor at the subject's position and pointing it back at the camera to measure the light falling directly onto the subject. This method is invaluable for determining the actual exposure on the subject, independent of the light reflecting off their skin or background, and is the standard for studio and location work.
Reflected metering, on the other hand, measures the light bouncing off the subject and returning to the meter. While many modern Sekonic models can function in a reflective mode by entering the subject distance, this is generally a secondary function. Incident metering is the preferred technique for most photographers because it provides a more accurate representation of the lighting ratios affecting the subject, ensuring that you are exposing for the person or object in the frame rather than a random background element.
Step-by-Step Guide to Setting Up for an Incident Reading
To take an incident reading, you will need to hold the meter at the subject's head or chest height. Rotate the dome of the sensor so that it faces the camera lens, effectively making the device "invisible" to the light source while still capturing the illumination that will hit the subject. This positioning ensures that the light hitting the subject is the same light the meter is measuring, leading to a reliable exposure calculation.
Once the meter is in place, you must determine the angle of view. If you are using a standard lens, pointing the meter directly at the camera lens is sufficient. However, if you are working with a wide-angle lens, you should point the meter at the edge of the lens hood to capture the broader field of light. For telephoto shots, you can generally keep the meter aimed at the camera since the narrow angle of view aligns with the lens perspective.
Interpreting the Display and Setting Aperture or Shutter Speed
After taking the reading, the Sekonic meter will display a specific f-stop value at a specific shutter speed, such as f/2.8 at 1/125s. This combination represents the optimal exposure for the scene based on the ISO setting you programmed into the meter. The key to using this data effectively is to maintain the total exposure value while adjusting the individual settings to match your creative or technical needs.
For instance, if you need a deeper depth of field for a landscape shot, you can change your aperture to f/11. By doing so, you lose "stops" of light because a smaller aperture allows less light through the lens. To compensate for this light loss and maintain the correct exposure, you must then slow down your shutter speed to a slower fraction of a second, such as 1/15s, or increase your ISO sensitivity. The meter allows you to "dial in" your chosen aperture or shutter speed, and it will immediately display the corresponding value you need to adjust to, keeping the exposure locked in.
Working with High-Contrast Scenes and Ratio Measurements
One of the most powerful features of a Sekonic meter is its ability to calculate lighting ratios, which is essential for managing high-contrast scenes. In portrait photography, for example, you might want to keep detail in both the highlights on the forehead and the shadows under the chin. To measure this, you take an incident reading for the key (main) light and record the value. Then, without moving the meter, you take a reading for the fill light (usually a reflector or a secondary light).
