How to Use a Light Meter

Here are the steps on how to use a light meter to achieve correct exposure every time, from landscape photography to portraiture.

A light meter is one of the best tools a photographer can have. It accurately measures the lighting in the scene, so you can use the right camera settings and achieve proper exposure.

Most cameras already have this tool built into their bodies. So you might probably be thinking if an expensive handheld meter is still necessary.

As a hobbyist photographer, I want to share that this is also one of my concerns back when I was still starting in the industry. However, trust me when I say that a handheld light meter is worth the cost. 

It provides the exact lighting information because it measures the light that falls directly onto the subject. In contrast, an in-camera meter only calculates the light that bounces off the subject, which gives a misleading reading.

But no matter how good a handheld light meter is, it’s essential that you learn how to use it properly. 

Keep on reading as I walk you through the steps on how to use a lightmeter.

What Is a Light Meter?

Sekonic Flashmate Light Meter

A handheld light meter is a device that evaluates light intensity to determine the proper exposure. It works by measuring both incidental (light falling on a subject) and reflective light (the light that the built-in camera meter calculates) that hits the white dome. This provides the ideal aperture and shutter value that you can set on your camera for achieving proper exposure.

The problem with most built-in camera meters is that they only take a reflective reading. Then, they calculate light intensity based on the midtones (grey) in an image. So if you constantly change the amount of greys within a frame, the camera meter will offer a different reading every time—even if you are simply reframing the same subject.

In contrast, a handheld light meter knows exactly where the bright (highlights) and dark areas (shadows) fall in relation to each other. It precisely tells you which parts of the subject are too light or too dark to retain detail. Thus, it provides a balanced reading of the light within a scene, which ultimately helps you expose the image properly.

What Are the Different Types of Handheld Light Meters?

Handheld light meters are available in two types—incident and reflective.

Incident Light Meter

An incident meter calculates the intensity of light that falls on the subject. It works by placing the meter in front of the subject. Then, it will automatically evaluate the light coming in the white dome of the meter, also known as a lumisphere.

An incident meter disregards how light or dark the subject is. This way, it can reduce errors caused by a backlit scene when metering. A built-in camera meter cannot perform this type of metering.

Reflective Light Meter

A handheld light meter can also measure the intensity of reflected light, similar to a built-in camera meter. A reflective meter is not as accurate when evaluating the amount of light over a larger area. However, it can still help you achieve the correct exposure, especially in situations where the light varies greatly throughout the scene.

This type of light meter can detect light through three different modes:

  • Matrix or Evaluative Metering – It divides the whole frame into separate areas. Then, it looks at the light intensity of each area and averages it.
  • Center-Weighted Metering – It is similar to matrix metering, but with an emphasis on reading the amount of light in the center of the frame. 
  • Spot Metering – It allows you to choose a specific focal point to measure exposure. However, it only calculates the light at that particular small area of a frame.

Most handheld light meters can switch between these modes easily. However, do note that they can read a smaller area compared to an in-camera light meter.

Choosing between these metering modes will depend on what you need and the type of photography that you do.

How To Use a Light Meter?

There is no one right way to use a light meter. You can set it to measure varying light conditions in different scenes.

With that said, I will include the basic steps on how to use a light meter to calculate incident light below.

Set Your Camera to Manual Mode

First things first, make sure to set your camera to manual mode or shutter priority mode. Select your preferred ISO and color temperature based on the light source that you want to measure.

Adjust ISO or Aperture 

Once you have set the initial camera settings, adjust the ISO on the meter to the same value on the camera.

If you want to control the depth of field, you also have the option to enter your desired specific aperture on the light meter.

Take a Reading

Turn the knob around the lumisphere (white dome) of your light meter to let it protrude. Then, hold the light meter in front of your subject and point it towards where the light is coming from. 

You can now press the measure button or metering button to read the light falling on the subject.

If you are using multiple light sources, you can calculate the light intensity individually by pointing the meter towards each one.

Dial the Exposure on Your Camera

After that, go back to your camera and adjust its exposure settings. Usually, you can change the shutter speed based on the reading given by the light meter. Once done, you can now photograph the subject and ensure proper exposure.

Take note that you don’t have to get a new reading if you are just reframing the same subject. Just keep on shooting and focus on the composition of the frame.

Only take a new meter reading if the lighting source changes, whether it gets brighter or darker.

How to Use a Hand Held Light Meter in Landscape Photography?

Now, let’s talk about how to use a handheld light meter in different types of photography.

Take note that the steps above are still applicable to incident meter reading. However, I will share some additional tips below that are geared towards a specific photography genre.

Incident Meter Reading

If you want to take properly exposed landscape photos, an incident light meter is one of the best tools to have. It measures the whole range of light within the scene and gives an accurate reading.

Hold the light meter in front of you and the camera. Then, press the metering button to read the results. After that, make sure to set your camera’s settings to match.

As much as possible, avoid pointing the white dome towards direct sunlight as it can result in an underexposed image. However, if direct sunlight cannot be avoided, try to cover the dome with your hand or any shade to get an accurate reading.

Reflective Meter Reading

I recommend using a reflective meter with the ability to use spot metering for an exact reading.

Place the meter at three different areas within the scene, namely the brightest highlights, the darkest shadows, and the midtone greys. 

Make sure the light meter remembers each reading by pressing the memory button after every exposure. 

Once you have collected the measurements, press the average button. The reflective meter will automatically calculate the average from the data to give you the perfect exposure setting. Simply set those same values on your camera to ensure proper exposure.

It can be pretty challenging to take three different readings manually, especially if you are not familiar with dynamic range.

Fortunately, your camera can instantly process it, owing to its built-in meter. Simply take note of the reading for each area, then calculate the average to get the proper exposure.

How to Use a Hand Held Light Meter in Portrait Photography?

Unlike landscape photography, portraits consist of human subjects. It is essential that they are properly exposed to make them stand out from the scene.

Here are the steps on how to use a light meter in portraiture.

Incident Meter Reading

A light meter is an excellent tool for portrait photographers as it can measure the different lighting on the subject’s face, instead of focusing on the dominant lighting.

To get the correct exposure, hold the meter in front of the subject’s face and point it towards the light source.

Press the metering button and you are done! You can now adjust the camera settings to achieve properly exposed images.

However, if you wish, you can expose one stop higher than the reading. Doing so is perfectly fine when it comes to portraits since it makes the scene and final photo brighter.

Reflective Meter Reading

You also have to take three separate readings of the subject in portraits, just like the reflective reading in landscapes.

Place the meter in the lightest areas, darkest spots, and midtones. Make sure to remember each reading, then calculate the average to get the camera settings for proper exposure.


Light meters are invaluable tools to every photographer, not just the professionals. They offer an accurate reading of the lighting with just a few button clicks. Thus, they are especially handy in situations where you need to get the exposure spot on.

However, like any other tool, it’s best if you know how to use a light meter properly to take full advantage of its benefits. I hope this article helped you remember the basic steps to follow when measuring light intensity.