How to Use Light Meters in Photography

Light meters are used to measure the amount of light between a subject and your camera, giving you the proper shutter speed and aperture settings to take a perfect picture. But not all meters are the same, and the readings you get could be different depending on which type you use.

Difficulty: Moderate

Instructions

In-Camera Meters

1. Select the correct film speed using the film speed (ISO) dial on the top of your camera. Some in-camera meters read the speed automatically if you're using a DX-encoded film cartridge.

2. Set the meter settings to either aperture, shutter speed or automatic. In the aperture setting, the light meter sets the aperture automatically, and you have to set the shutter speed. Using the shutter speed setting automatically sets the shutter speed, and you have to set the aperture. Automatic selects both settings for you.

3. Press the shutter button on the top or side of your camera half way down to take a reading and lock onto the subject. Make sure you don't push it all the way down or hear a click, which means you've taken a picture.

4. Use the meter readings to set either your shutter speed or aperture if the camera is not set to automatic.

Spot Meters

5. Adjust the film speed (or ISO) dial on the top of the meter to the speed of the film you're using.

6. Measure the light between the camera and you subject by pressing the button on top of the light meter. This gives you an aperture and shutter speed.

7. Take a second reading from the subject back to the camera. There may be some cases where you can't do this, such as when photographing wildlife.

8. Average the two readings, and set the shutter speed and aperture on your camera.

Tips & Warnings

• A spot meter only reads the light from one specific area. You may want to take several readings and average them out to get the correct settings. Overall, though, the spot meter gives you more accurate readings than an in-camera meter.