Photometric skills of SLR camera

Can you measure light? Which metering method is good? What I want to share with you is the metering skills of SLR cameras. Welcome to learn from them!

Photometric skills of SLR camera

Don't point to the sky, don't point to the darkest place. Try to catch the middle value.

According to the subject matter you shoot, use the metering mode (weighing metering, spot metering, center button metering ...).

If you are not sure about photometry, please use AE lock to expose and lock the surrounding gray things before shooting.

Try not to measure light on white or black objects, otherwise remember to subtract EV from black and add EV to white.

Exposure compensation is also an exposure control method, generally around 2-3EV. If the ambient light source is dark, you can increase the exposure value (such as+1EV, +2EV) to highlight the clarity of the picture.

Photometric principle of camera

The metering principle of cameras (digital and various films) is not complicated. The most important thing is to understand what the camera's metering system (or exposure meter) is based on! In layman's terms, it is how the camera "thinks" what it sees when measuring the light of a scene.

Remember: all cameras will default all the objects they "see" to the gray with a reflectivity of 18% (the technical term for photography is "middle gray") and use this as the benchmark for photometry. That is to say, in the "eyes" of the camera, all the subjects are gray, and the purpose of exposure is to correctly restore this gray.

Why is this special 18% ash? Because the color of 18% ash is the same as the average reflected light of human skin (16 ~ 20%), and people are the most frequently photographed objects. The reflectivity of other objects, such as silver is 96%, drawing white paper is 75%, and pure black is 3%. )

When the exposure meter works, it depends on whether the reflectivity of the subject is 18%. If the reflectivity is 18%, then the measured value is very accurate. According to this value, the color and tone of the subject will be truly restored. Therefore, for our skin and ordinary colorful scenery, this exposure based on gray tone is very accurate.

If the reflectivity of the subject is not 18%, then the value measured by the camera metering system is inaccurate. If the exposure is directly based on this value, the tone and color of the picture will be distorted: for example, when shooting white snow fields and dark coal fields, the camera will restore them to gray and focus directly, and gray snow fields and coal fields will often appear.

Tips: Some tips for reasonable photometry in digital photography;

① To shoot a snow scene, you can press the shutter half way in front of your hand, that is, measure your skin, and then press the shutter, which is the kind of snow you want to shoot, so the snow is white. Similarly, when taking a portrait in black and white, you should measure your face first, and then take a composition. )

② When shooting bright objects, the aperture should be higher than the index recommended by the exposure meter by 1 ~ 2, while for dark objects, the exposure should be reduced appropriately.

(3) Taking photos in sunny seasons will bring great contrast to the photos, so it is necessary to measure the light of the bright and dark parts of the scene separately and take photos with their average exposure index.

Tip: Remember the following substances, whose reflection values are close to 18%, which may be very useful for shooting under complex conditions:

Grass (mow the grass! ), but note that it is not dark green, especially green or yellow grass;

② Most pale green leaves or plant leaves;

③ part but not all of the trunk;

(4) Old and repaired asphalt roads and concrete (this is very useful);

⑤ Wood that has been left for a long time and has not been oiled;

6. Red/brown bricks, including cement walls;

⑦ Dry leaves.

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