How to choose your camera’s exposure mode

How to choose the exposure mode of your camera

The first step in getting started with photography is to learn to use the camera in your hand. Nowadays, digital cameras are becoming more and more powerful. Let alone novices, even experienced veterans may not necessarily know the function of each function on the camera. Among all these complicated buttons, the most important one is the exposure mode. Fully automatic? Program automatically? Aperture priority? Shutter priority? Fully manual? If you haven’t figured out the relationship between them yet, you might as well read this article to catch up.

In order to explain the characteristics and applicable scope of various modes, we need to introduce several basic concepts - the three elements of exposure, namely exposure length, aperture size, and sensitivity. Three key factors will determine the final imaging result.

Element 1: Aperture size

That is the size of the clear aperture of the lens, usually expressed by the f value, f = focal length of the lens / diameter of the effective aperture of the lens. The smaller the f value, the larger the aperture, and the greater the unit light transmission; the larger the f value, the smaller the aperture, and the smaller the unit light transmission. For example: the aperture of f/1.8 is larger than that of f/5.6, and the amount of light transmitted per unit time is greater!

At the same time, aperture is also an important factor that affects the depth of field. Keeping other factors unchanged, the larger the aperture, the shallower the depth of field (the more obvious the blur effect); the smaller the aperture, the deeper the depth of field. (The wider the clear range).

A large aperture can create blur, while a small aperture can easily produce starbursts.

It can be seen that we can achieve two purposes by controlling the aperture. One is to control the amount of light entering, and the other is to control the depth of field effect.

Element 2: Shutter speed

Shutter speed is the exposure time, usually expressed as a fraction. The faster the speed, the shorter the exposure time and the less the amount of light; the slower the speed, The longer the exposure time, the more light is transmitted. For example, a shutter speed of 1/250s is faster than a shutter of 1/30s, which means less time for light to pass through, so less light is obtained.

At the same time, the shutter speed also determines the capture effect of the camera. If we want to capture fast-moving objects, we should use a high-speed shutter.

Element 3: ISO

Sensitivity (ISO), this is a concept that has been passed down since the film era, representing the sensitivity of the photosensitive material to light. The higher the ISO, the more sensitive it is to light. The more sensitive the element is to light, the less light is needed to achieve the same effect; the lower the ISO, the slower the photosensitive element is to light, and the more light is needed to achieve the same effect.

However, due to the limitations of the photosensitive elements of digital cameras, the picture is prone to noise at high ISO, so many photography enthusiasts try to lower the ISO when shooting to obtain a purer picture. The meaning of ISO is to liberate the combination of aperture and shutter by improving the sensitivity of the photosensitive element when the light conditions are extremely poor.

You may wonder why the topic of the article is "Camera Exposure Mode", but you still have to listen to these boring basic knowledge repeatedly? Don’t take it for granted, this is exactly the point of the question “Teach you how to choose your camera’s exposure mode.”

1. P mode and automatic mode: suitable for novices or lazy students who don’t want to set up a camera

In our common sense, we often think that P mode is the novice mode. There are so many Reasonable. Although the P gear is slightly different from the fully automatic gear, their principles are basically the same.

The fully automatic mode is also the fool mode. It relies on the measurement of the camera environment to formulate a set of modes to ensure sufficient exposure. It will automatically select white balance, aperture, shutter, ISO, flash and other means to promote shooting. Success, the intent of the shot will not be taken into account. In P mode, the camera generates a relatively suitable exposure combination of aperture and shutter based on the shooting environment and the internally stored exposure data. It looks a little more advanced, but in fact it is a fool mode that only needs to press the shutter.

Of course, this mode is suitable for novices who know nothing about it, or "lazy" students who have no interest in camera settings. However, using this method does not mean that you are not willing to make progress. Some people think that the camera's program exposure function is already so powerful, why not take advantage of this and spend more time improving composition? Mobile phone photography is becoming more and more powerful, isn’t it all based on the principle of P mode? It seems to make some sense.

2. Aperture priority mode: Suitable for students who want to learn photography and want to have an in-depth understanding of light

As the name suggests, the photographer first determines the shooting aperture according to his own needs, and then the camera Give your aperture a shutter speed that ensures a reasonable exposure.

When using aperture priority mode, the first thing to consider is the change of depth of field. Different themes must be expressed through different depth of field. For example, use a large aperture to blur the background of a portrait:

Or, among landscape photographers, use a small aperture to ensure sufficient depth of field:

It should be noted that when shooting with a small aperture, , the corresponding shutter speed will also be slower, and a tripod is often needed to fix the camera.

Even if you use aperture priority mode, you should also pay attention to the shutter speed. The camera will only give a recommended shutter speed based on the flux of light. It cannot accurately determine the shooting environment at the time, such as a low-light environment. The camera may give a lower than safe shutter speed based on your aperture, causing hand shake. .

The reason why this is the most suitable exposure mode for students who are just learning photography is because it involves depth of field control, exposure combination and other settings. Slowly explore these settings every time you shoot. The relationship between these factors can help you better understand exposure.

3. Shutter priority mode: used to create special photographic effects

Contrary to aperture priority mode, shutter priority mode determines the shutter speed first, and then the camera gives an appropriate aperture. size.

According to our past understanding, taking pictures is to freeze a wonderful moment. Indeed, sometimes it is that simple. For example, when shooting sports scenes, facing high-speed moving objects can only be captured with the same high-speed shutter.

When we use a high-speed shutter, we must pay attention to whether there is a large enough aperture or ISO to ensure the exposure.

By controlling the shutter, you can not only freeze the moment, but also "delay" time. For example, when shooting running or racing, using a slower shutter and following the movement of the subject in the picture can create a "clear subject. "Background blur" focusing effect.

Or use a slow shutter speed and rotate your camera while shooting to turn ordinary images into abstract ones.

4. Manual mode: suitable for students who are serious about photography and have the patience to persevere

At this point, you can really start to play photography. To put it bluntly, photography is about using light and shadow to play a game with the world, and manual mode allows you to take the rules of this game into your own hands.

Here is a word for everyone. You should have a deep understanding in the future that there is no accurate exposure, only appropriate exposure. The several automatic modes and semi-automatic modes mentioned earlier actually involve the camera. The camera helps you decide some parameter settings to make your picture "correct" and standard.

But sometimes we just need to overexpose, underexpose, or blur the picture in order to better express our picture. At this time, it can only be achieved through manual mode.

Since we are in the digital age, there is basically no pressure in manual mode. Now the camera’s built-in metering function is very powerful and can be used as a shooting reference.

This silhouette is a very good example. Through manual exposure, ensure that the background and foreground are lit, and the main character becomes a silhouette. If you leave it to the camera itself, it's likely that the characters will be exposed accurately, but the background will be too blown out.

Another use of manual mode is B door, which is a common long exposure. During the shooting process, which can last up to several minutes, it requires the photographer to make an independent judgment and control of the picture, try repeatedly, and constantly adjust until the picture obtains the appropriate exposure. This cannot be judged through the camera's built-in function. .

Summary

For novices, how to understand the different exposure modes of the camera and how to make reasonable choices, we can start from these points:

< p> (1) If you are afraid of trouble and don’t want to spend too much time on parameter settings, please use the P file;

(2) If you want to learn photography and understand the relationship between the camera and light and shadow, And to control the depth of field, please use the aperture priority mode;

(3) If you need to control the exposure time, such as shooting high-speed sports, slow-speed special effects, etc., please use the shutter priority mode.

(4) Of course, if you want to take photography seriously, you must learn to use manual transmission.

;