How do you use a light meter to measure the intensity and color temperature of TV lighting?

1 What is a light meter?

A light meter is a tool that measures the luminance or illuminance of a light source or a surface. Luminance is the amount of light reflected by an object, while illuminance is the amount of light falling on an object. Light meters can be either incident or reflective, depending on how they measure light. Incident meters measure the light that hits the meter directly from the source, while reflective meters measure the light that bounces off the subject. Incident meters are more accurate and consistent, as they are not affected by the color or texture of the subject.

2 How to use an incident light meter?

To use an incident light meter, you need to place it in front of the subject, facing the main light source. You can either hold it by hand or attach it to a stand. Then, you need to set the ISO and shutter speed on the meter, and press the measure button. The meter will display the aperture value that you need to set on your camera to get a proper exposure. You can also use the meter to compare the intensity of different light sources, such as key, fill, and back lights, by moving it around the scene and noting the readings.

3 How to use a reflective light meter?

To use a reflective light meter, you need to point it at the subject from the camera position, and press the measure button. The meter will display the aperture value that you need to set on your camera to get a proper exposure. However, reflective meters are not very reliable, as they can be fooled by the brightness or darkness of the subject. For example, if you point the meter at a white wall, it will give you a low aperture value, making the image too dark. To avoid this, you can use a gray card, a neutral-colored card that reflects 18% of the light, and point the meter at it instead of the subject.

4 What is color temperature?

Color temperature is a measure of the hue or color of a light source, expressed in Kelvin (K). It ranges from warm (red) to cool (blue) colors. For example, a candle has a color temperature of about 1800 K, while a clear sky has a color temperature of about 10000 K. Different light sources have different color temperatures, and they can affect the color balance and mood of your images. For example, if you mix tungsten lights (3200 K) and daylight (5600 K), you will get an orange and blue tint in your images.

5 How to measure color temperature?

To measure color temperature, you need a color meter, a device that measures the color spectrum of a light source and displays its color temperature in Kelvin. You can either use a dedicated color meter, or a light meter that has a color function. To use a color meter, you need to place it in front of the light source, facing it directly, and press the measure button. The meter will display the color temperature of the light source, and you can compare it with the color temperature of your camera or your white balance setting.

6 How to adjust color temperature?

To adjust color temperature, you have two options: change the light source or change the camera setting. You can change the light source by using different types of bulbs, filters, gels, or modifiers that alter the color of the light. For example, you can use a blue gel to make a tungsten light cooler, or a orange gel to make a daylight light warmer. You can also change the camera setting by using the white balance function, which allows you to adjust the color temperature of the camera sensor to match the light source. For example, you can use the tungsten setting to make the camera cooler, or the daylight setting to make the camera warmer.

7 Here’s what else to consider

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