How does Canon 60D measure light?

You can refer to the following methods:

How to choose metering mode;

First of all, let's understand the differences between several measurement modes:

1. Evaluation metering is the standard metering mode of EOS cameras, which is suitable for most subjects. After the camera detects the comprehensive lighting elements such as the position, brightness, background and lighting conditions of the subject in the viewfinder, it sets the correct exposure for the subject.

2. Due to backlight and other reasons, partial metering is very effective when the background is brighter than the main body. Photometry is concentrated in the center of the viewfinder, covering a part of the center of the viewfinder.

3. Spot metering is used to measure the specific part of the shooting object or scene. Photometry is concentrated in the center of the viewfinder, covering a small area in the center of the viewfinder.

4, the central focus average metering focuses on the center of the viewfinder, and then averages the whole scene.

Secondly, let's look at how to choose:

1, evaluation photometry: In most cases, evaluation photometry can get basically accurate exposure value. So it is suitable for shooting most scenes with even light and dark.

2. Partial photometry: generally used for shooting backlight films.

3. Spot metering: If you are sure to ignore the surrounding parts, partial metering and spot metering can get a more accurate exposure value. This can keep the subject exposed correctly, and the background will be too bright or too dark, which is generally used for macro and close-up shooting.

4. Center key average metering: If you are sure that the surrounding parts need to be considered a little, you can choose center key average metering. This subject is not particularly ideal, but the surrounding and background will not be too bright or too dark, and some consideration will be given. Suitable for shooting in the morning, sunset and sunset.

When choosing the metering mode, it should be noted that once the scene or the desired effect does not meet the standard of metering mode, it is necessary to predict the light result. At this time, exposure compensation is the best choice, and a wide range of plus or minus 5 gears will make you very satisfied.

In addition, in the actual shooting process, the choice of metering points in the latter three modes has a great influence on the metering results (for example, when metering, its coverage area only reaches 4%), so we must pay attention to it when shooting.

Also, in the evaluation metering mode, half-pressing the shutter will lock the metering result and exposure combination, while the latter three modes are not, and will be locked only after you press the exposure lock key. Therefore, before moving the composition in the state of selecting the last three metering modes, it must be locked before moving the composition.

Extended data:

According to the different placement positions of metering elements, metering methods can generally be divided into external metering and internal metering:

(l) External metering: In the external metering mode, the optical paths of the metering element and the lens are independent. This metering method is widely used in head-up viewfinder shutter cameras with sufficient sensitivity and accuracy. Single-lens reflex cameras generally do not use this metering method.

(2) Internal metering: This metering method is based on the lens, that is, TTL metering, which is consistent with the shooting conditions and can be automatically corrected when the camera lens changes, the shooting distance changes and the color filter is added. At present, almost all single-lens reflex cameras adopt this metering method.

Baidu Encyclopedia-Canon 60D

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