Spot Metering – A Beginner’s Guide on How to Use it

Using the spot metering mode on your digital camera can help you make better photos. Spot metering helps you set more precise exposures than other metering modes will. This is because you can narrow the area the camera meter reads from more than with evaluative or center-weighted metering.

Spot metering is a metering mode I use very frequently. I have a function button on the front of my camera programmed to use spot metering. This allows me to switch quickly between Matrix metering and spot metering. I have my camera set to matrix metering by default and will make the switch to spot metering mode when I feel the need to.

In this article, I’ll explain why I like to use the spot metering mode along with matrix metering. Matrix metering is called evaluative metering mode on Canon cameras. This will help you get correctly exposed photography more often than if you are only using the default metering mode on your camera.

All the camera metering modes are helpful. But if you only use partial metering, Matrix metering, or evaluative metering, you will not always get the correct exposure. Using manual mode rather than aperture priority or another automatic exposure mode will also help you be more accurate in getting correct exposures when you take a meter reading.

More About Exposure Metering Modes on Digital Cameras

To make a correct exposure, a camera’s sensor must receive the right amount of light. When the sensor in a camera is exposed to too much light, the photo will be overexposed. If it is exposed to not enough light, the image will be underexposed. Properly controlled exposure metering helps you or your camera set a correct exposure.

A correct exposure is what you decide is right. Photography is subjective. Many photographers aim to have a broad range of tones that contains detail at both ends of the scale. They expect that this is what makes an image properly exposed.

This often depends on the light. Sometimes the light is soft and even. It’s easy to get a correct exposure reading when the light is like this. At other times in your photography experience, you’ll be making images where the light is hard, and there is high contrast. Light meters will not always provide you with the best exposure in these circumstances when they are set to the default mode.

Setting the best metering mode for the light you are working in helps you adjust the aperture and shutter speed for the best exposure settings. In hard light, spot metering is often the best option. When you use spot metering, you can choose the focus point of the meter. The exposure calculation is likely to be more precise and will properly expose your image.

How Metering Modes Work on a Digital Camera

A camera’s metering system is designed to read light reflecting of things as though it is all a particular tone of gray. This is known as eighteen percent gray or middle gray. Camera meters are not intuitive. They are programmed to read light as though it’s reflecting off middle gray no matter what tone your subject is. Sometimes this will cause exposure problems. Using the spot meter in these situations can help you with better camera settings.

When you point your camera at a subject, the metering mode you choose determines how much of the frame the exposure meter reads from. In evaluative or matrix metering modes, light in the whole frame is measured across many different points. The camera will calculate the exposure based on the average of these readings. 

With center-weighted metering,  the exposure meter reads the light from about sixty percent of the frame, weighted in the center.

Spot metering reads the light value from a single point of between one percent and five percent of the entire camera frame. So you can be very precise about the point where the camera will read the light from. This can help set the aperture and shutter speed. Or, if you are using an automatic exposure mode, you can adjust the exposure compensation for more accurate exposure.

Spot metering is the best choice when you don’t want to make an exposure reading from the entire scene or even a large part of the image.

How Do I Use the Spot Metering Mode

In high contrast scenes, using the spot metering mode will help you take a reading from a tiny area. And make a better meter reading than if you use other exposure measurement modes.

Select spot metering from an external control on your camera or in the camera’s menu system. It makes sense to use it in high contrast images more so when the light is more even. You can select the point you want to meter from that is most important to your image. Once you have taken a spot meter reading, you can use manual mode to set your exposure, or you can let the camera do it for you if you use any of the automatic modes. You can always use the exposure compensation feature on your camera. This helps avoid having to correct the exposure in post-production.

As I mentioned earlier, I like to use the spot metering mode on my cameras often, so I make it easy to select this metering mode. On some brands, it’s easier than on others. Use your manual to help you find how to set the spot metering mode.

Some cameras position the spot meter pint in the central part of the frame. On other cameras, it will follow the focal point that is active when you are using the autofocus mode. You’ll need to research this yourself. Because it is important to know where the small area is that you are taking a spot metering reading from when you don’t want a reading from the entire frame.

Is Spot Metering the Best for Portraits?

Spot metering is only going to help you with the exposure settings when you can make sure it is positioned on the part of your subject that’s most relevant. Metering from the wrong point is not going to give you the best metering results in your photography.

When taking portrait photography, I always use spot metering mode. First, I’ll take a reading using the matrix metering mode to get an overview of the light on my subject and scene. Then I’ll switch to spot metering mode and take an exposure reading from the face of my subject.

This reading will determine what a good exposure setting will be so I can capture their skin tone, so it looks good. This will be different for caucasian skin than for Asian skin or darker skin tones. 

With portrait photography against a light or a dark background, using spot metering mode is best. This will help you avoid reading light from the background and take a reading only from your subject’s face. This is why it’s so important to know how your camera manages the spot metering point. Does it follow the AF point? Or does it remain on the center spot? Knowing this will make your metering work better for you.

If you do not know where your spot metering is taking a reading from, the results can be worse than when you are taking a reading from the entire scene. Positioning the spot precisely where you want it, in portrait photography, this is on the subject’s face, you will get the best results.

Why Use Spot Metering Mode for Your Photography?

When the light is strong and hard, like outdoors on a sunny day, your camera’s sensor may not be able to record a full tone range from the entire scene. You’ll need to choose what area of your image to make your exposure for. This can also help you be more creative with your photography because you are not relying on the averaged metering mode to render an image in a possibly boring way.

If your subject is in the shade and there’s a large part of your scene in the sun, you can use the spot metering mode to take a light reading from your subject. Then you can set the exposure so your subject will be well exposed. In scenes like this, if you use evaluative metering, your subject may not be exposed properly. This is because of the strong influence of the sunlight in the frame.

Making a spot meter reading can help you set the best exposure when you have subjects in your frame that are in high contrast. Photographing items in the same frame that are black and white, you might not get a good exposure on both. The white things might be too bright, or the dark things might be underexposed. This will depend on the light and also on the quality of the sensor in your camera. Higher quality sensors are more capable of recording a broader tone range in a single photograph.

Conclusion

By using the spot metering mode, you can choose the best place to take a light reading from. Once you’ve made the reading, you can then best calculate the exposure settings and manage them, so the most important part of your composition is well exposed.

The more comfortable and confident you are using your camera’s metering system, the better your photography will be. Managing exposure is also very important. Learning the metering modes well will really only help you when you know how to set the exposure controls as well. Here’s a series of videos that will help you learn to manage the exposure settings like a pro on your cameras, no matter what kind of photography you enjoy.

To learn more about using the spot meter and other metering modes on your camera and when to use them, check out our 365 Days of Photography Course. In this course, I teach in-depth about how best to use the metering system in your digital cameras and why it’s important to understand this. 

Here is another related article that provides a great deal more information on how exposure metering works in cameras.