A handheld light meter offers photographers greater precision and creative control over their images. Using a handheld meter allows you to create well-exposed images even under complex lighting situations that can trick built-in camera meters. Despite looking complicated, a few simple techniques will have you using a handheld light meter with ease, whether you’re shooting landscapes, portraits, or still-life.
What is a Light Meter?
A handheld light meter is a separate tool for evaluating light intensity and calculating exposure. At its simplest, it calculates an aperture and shutter value that you set your camera to for a correct exposure of a given scene. It can also provide all the aperture and shutter combinations that match an exposure value.
Modern cameras have built-in light meters that allow photographers to make well-exposed photos without a separate tool. This built-in circuitry works well for most of the situations that a photographer may run into. But a handheld light meter is designed to do one job extremely well. That job is to precisely evaluate levels of light and relate them to shutter and aperture settings to create a well-exposed image under even the most difficult lighting conditions.
All cameras have a limited dynamic range—a specific maximum level and minimum level of brightness—that can be captured. A handheld light meter lets you know exactly where the bright and dark areas fall in relation to each other. This can tell you precisely which areas of the image will be too light or dark to hold detail. Having this information will help you expose for the important areas of an image or let you know when to use a high dynamic range technique to expand your camera's dynamic range.
You can use the information from your light meter to help you choose how light a subject is. For example, if I take a reading of a white piece of paper, it will show up as middle grey when photographed. That is because all light meters are calibrated for middle grey. So if I want that white piece of paper to be white, I need to overexpose it and the light meter will tell me how much by which to overexpose.
Types of Handheld Light Meters
There are two categories of light meters: incident and reflective.
Incident Light Meters
An incident meter reads the amount of light falling on the subject. You hold the light meter in front of the subject and the meter will evaluate the amount of light that reaches its white dome, known as a lumisphere. By metering this way, you will disregard how light or dark your subject is and help eliminate errors caused by a back-lit subject. A built-in light meter is not capable of this type of metering.
Reflective Light Meters
A reflective light meter records the light levels that are reflected by the subject. That means light travels from its source, bounces off the subject, and then is picked up by the light meter. A camera's built-in light meter is a reflective light meter. There are different types of reflective meters based on how much of the frame is metered:
- Matrix or Evaluative Metering breaks a frame into zones and uses an algorithm to judge exposure.
- Center Weighted gives the center of the frame more importance when measuring exposure.
- Spot metering looks only at a small area of a frame to measure exposure.
A built-in light meter can switch between these patterns. A handheld light meter only does spot metering, incident metering, or both, such as the one shown in the examples here. In addition, handheld meters can read an area of the image which is much smaller than that of a camera's built-in meter. This ability to read such a small area of a scene will help you evaluate the relative brightness or darkness of even the smallest details.
Now that we’ve covered how a handheld light meter works, let’s put it to practical use in three different scenarios. We’ll cover landscapes, portraits, and still-life, showing how to use either the incident or reflective spot meter.
1. How to Use a Hand-held Meter in Landscape Photography
Incident Meter Reading
An incident meter is all you need to get highly accurate exposure settings for landscape photos. The simplest technique is to hold the light meter out in front of the camera, making sure that the same light falling across the scene also falls on the lumisphere. Then press the meter button. Read the results on the meter and set your camera's shutter and aperture to match. Now you have your camera set to accurately expose your scene.
The only thing you have to be careful of is not to have the sun shine directly on the lumisphere because this can be too bright and cause you to underexpose your image. One way to avoid this is, when you see a bright sun spot on the lumisphere, hold the white dome partly in your shadow. With a landscape photograph (and unlike the examples below) we usually can't move the light meter to all the places we'd like to measure. Moving the meter out of direct sunlight gives a better measurement of the amount of light in the shadow areas in the scene, which is where it's most important to retain detail.
Reflective Spot Meter Reading
When using a spot meter in landscape photography, you will want to take several readings from different areas of the scene. Take readings for most important areas like the darkest shadow area, the brightest highlight area, and the mid-tone areas. Commit each reading to the meter's memory by pressing the memory button after every reading. Then use the average button on the meter to provide a final exposure value and put those settings into the camera. This technique allows you to take in a lot of light intensity information and quickly process it without tedious manual calculations. Once you get used to looking for areas of differing brightness in a scene, you can take these readings quickly.
I have converted my landscape photo to black and white because I think it is easier to consider exposure and tones without the interference of color.
2. How to Use a Hand-held Meter in Portrait Photography
Incident Meter Reading
In portrait photography, an incident meter is an invaluable tool. You can use it to quickly and easily grab a reading of the light falling on a person’s face. All you have to do is hold it in front of the subject with the lumisphere facing the camera and press the measure button. That’s it; the meter will tell you how much light is falling on the subject. If you want the subject lighter than middle grey, just overexpose by one stop.
Reflective Spot Meter Reading
In portrait photography, you will take a few reading from key areas of the the portrait. Meter the highlights of a person’s face, their hair and the highlights and shadows on their clothes. Commit each reading to the meter's memory by pressing the memory button after every reading. Then use the average button on the meter to provide a final exposure value and put those settings into the camera.
Here is a look at my portrait. I have converted it to black and white because I think it is easier to think about exposure and tones without the interference of color information.
3. How to Use a Hand-held Meter in Still Life Photography
Incident Meter Reading
In still life or product photography, an incident meter is handy tool. You can use it to quickly and easily grab a reading of the light falling on a subject. All you have to do is hold it in front of the subject with the lumisphere facing the camera and press the measure button. It does not matter how reflective or dark your subject is, you will get a good baseline exposure. If you want the subject lighter or darker, you can overexpose or underexpose the photo.
Reflective Spot Meter Reading
For still life photography, you will want to take several readings from different areas of the still life. Take readings for most important areas like the darkest shadow area, the brightest highlight area, and the mid-tone areas. Commit each reading to the meter's memory by pressing the memory button after every reading. Then use the average button on the meter to provide a final exposure value and put those settings into the camera.
Here is a look at my still life photograph. I have converted it to black and white because I think it is easier to see exposure and tones without the interference of color.
After working with your handheld light meter for these different types of shots, you won’t want to go back to your camera’s built-in meter. You’ll also start seeing the differences in exposure and the amount of time that you spend adjusting the photograph after it’s taken. Handheld light meters make a great tool for all photographers and should always be in your kit.
