Learning how to use a light meter will help you create beautifully lit shots every time. Discover different types of meters and how to use them.
It can be extremely frustrating when images turn out underexposed or overexposed. Images with blown highlights or shadows that are too dark can be edited, but they’ll never look as good as they would have with proper exposure in the first place. That’s why it’s important to get the exposure right from the start. In a situation where lighting is complex, a light meter can help you get properly exposed shots every time.
A light meter evaluates the lighting in a scene and calculates the correct shutter speed and aperture, two parts of the exposure triangle. It can be a handheld device or it can be built into the camera. Whether you’re shooting all day and need to account for changing sunlight, or you’re at an event like a concert with a wide range of light levels, a light meter will take away the guesswork so your images are correctly exposed every time.
Is a light meter necessary?
Not always, but using a light meter will give you more precision and greater creative control over images as they’re shot. Along with calculating the correct settings, a handheld light meter will let you know what areas of your photo will be dark and which will be light, helping you properly compose your photos.
Types of light meters.
There are two primary types of light meters. The first kind is an incident meter, which is held in front of the subject and measures light in that spot. It has a white dome on top called a lumisphere. This is what measures how much light is illuminating the scene.
The second type of light meter is a reflective meter, which is the kind built into a camera. All modern DSLR cameras have built-in meters that measure the light that reflects off the subject. Reflective light meters have some variance to them but most commonly fall into one of three types:
- Matrix (Nikon) or evaluative (Canon) metering is typically the default metering mode on most cameras. It works by breaking the frame into zones and taking readings of each zone. It’s important to note where the focus is set as the meter will prioritize this area.
- Center-weighted metering places importance on the center of the frame when measuring the light. It ignores the corners and the focus point. This type of metering is great for portrait or headshot photography or when the subject is backlit.
- Spot metering measures light from a small area around the focus point and ignores everything else. It’s great for small subjects or landscapes.
How to use an incident meter.
While a handheld meter may look complicated, it’s incredibly easy to use. Simply place the meter in front of the subject with the lumisphere pointing toward the camera.
If you’re not using a tripod, just point the meter toward where you’ll be standing. Push the meter’s button and set your camera to the settings the meter gives. If you’re not able to get to your subject, you can place the meter in the same light as the subject and measure that way.
When to avoid using an incident meter.
If the subject is in light that’s completely different from the light you’re shooting in, an incident meter won’t work (think shooting something on a brightly lit stage at night). In cases like this, you should use a reflective light meter instead.
How do I use a light meter for landscape photography?
When shooting landscape photos with a reflective light meter, avoid metering the highlights of the scene. This will underexpose the darkest parts, leaving them with less detail, and may introduce more noise. Spot metering works nicely for landscape photography as you can pick a point that’s not too bright and not too dark.
If you’re using an incident meter, walk a bit in front of the camera and point the meter back toward the camera. As long as you’re in the same light as your scene, you’ll be able to use the settings your meter provides. There’s no need to take a long walk into the scene you’re shooting.
How can I get proper exposure without a light meter?
If you don’t have a light meter on hand or in your camera, the “sunny 16” rule can help you get the correct exposure.
- Set the aperture for the conditions you’re shooting in.
- Sunny (hard shadows): f/16
- Partly cloudy (soft shadows): f/11
- No shadows: f/8
- Overcast: f/5.6
- Sunrise/sunset: f/4
2. Set the shutter speed for the reciprocal value of the ISO. For example, if the ISO is set to 200, the shutter speed will be 1/200. If the ISO is 100, then the shutter speed will be 1/100. (Tip: Read this article about ISO to learn more.)
Apps for light metering.
There are several high-quality light-metering apps available for your smartphone. Some have a separate device you plug into your phone to act as a lumisphere and turn your phone into an incident meter, while others act as a reflective meter without additional equipment. While a phone app may not be able to measure very dim light as well as a handheld meter, they get the job done for most situations.
Using a light meter will help you take the guesswork out of properly exposing your photos and will reduce how much editing needs to be done in post. It’s a tool that should be in every photographer’s kit and is well worth the investment.
