How to take photos with shallow depth of field with iPhone?

Using Apple mobile phone to take photos with shallow depth of field has a natural disadvantage compared with cmos camera from the hardware point of view, but similar effects can be achieved through some tricks.

Find out the principle of shallow depth of field blur effect. If you want to shoot a shallow depth of field effect, which is commonly known as the background or foreground blur effect, you need to find out how this effect is produced optically. Controlling the depth of field depends on three basic elements: aperture, focal length and shooting distance. The larger the aperture, the longer the focal length and the closer the shooting distance, the more obvious the shallow depth of field effect will be, which is the most basic photography truth. Then, after understanding this truth, we can analyze how to take a shallow depth of field effect with iphone.

The aperture of the iphone lens is different from that of the camera. It is fixed and cannot be adjusted. The so-called aperture value set on the mobile phone is actually virtual. Physical aperture cannot be enlarged or reduced at all. There is no mechanical aperture blade or electromagnetic aperture. Like other mobile phones, the aperture of the iphone is always kept at the maximum. For example, if the aperture of your mobile phone is marked as f 1.8, then its physical aperture is fixed at this value and cannot be changed. In this way, in fact, the lens aperture of the iphone is not small, and it is also a large aperture in the camera field, but why is the effect of direct shooting blurred? This needs to consider the focal length and shooting distance. If these two indexes are contrary to shallow depth of field, the blur effect brought by large aperture will be weakened.

Obviously, because the cmos size of the iphone is much smaller than that of the camera, in order to achieve a wider field of vision, it is necessary to use a shorter lens focal length than the camera or a shooting distance farther away from the subject. Therefore, even if the aperture of the mobile phone is large, the short-focus lens and long-distance shooting are placed here, it is impossible to directly shoot the blur effect of the large aperture like a camera.

At the same time, we should also understand that the physical focal length of the iphone lens is very short, which is said to be equivalent to 28mm or 50mm, but it is similar to these focal lengths from the perspective. However, due to the small size of cmos, the viewing angle will be greatly reduced compared with the same focal length of Quan Huafu, and a shorter physical focal length is needed to be equivalent to the viewing angle of 28mm or 50 mm, so we can't expect to take a shallow depth of field effect on the iphone with a long focal length.

Knowing this principle, we will know how to avoid the shortcomings of iphone and find a way to shoot shallow depth of field with it:

1, close to the subject, according to the principle of "the closer the shooting distance, the shallower the depth of field". This shooting method is more suitable for shooting some macro subjects. Because if you shoot an ordinary portrait, if the mobile phone is too close to the subject, it will cause trouble in composition, and you can only shoot the part of the character, while shooting a smaller object and shortening the shooting distance can just create a shallow depth of field effect. For example, shoot some flowers, insects, small still life and so on. You can take a shallow depth of field effect in this way.

But at the same time, we should also pay attention to the background of the subject as far away from the subject as possible. If the distance between the subject and the background is very close, the effect of shallow depth of field can not be achieved.

2. Use the built-in image algorithm of iphone to simulate the shallow depth of field effect. The so-called portrait mode, virtual aperture and other gameplay are unique to mobile phones. You will never find such a built-in processing mechanism on the camera, which is a virtual shallow depth of field effect produced by the powerful operation of the mobile phone. Iphone is not as powerful as hardware, and the software is also very powerful. These two aspects are undoubtedly much more powerful than cameras. Virtual algorithm can achieve a simulation effect similar to shallow depth of field.

However, this effect is not the real optical shallow depth of field effect, but the mobile phone uses software to automatically repair a picture for you, stripping the background from the main body and blurring the background.

3, use retouching app to do shallow depth of field effect. First take photos in the normal camera mode of the mobile phone, and then import the photos into the retouching app. Through the method of mask segmentation, the subject and background are distinguished, and the selection of background part is blurred, which can simulate the effect of shallow depth of field. This is also a method. This method is actually similar to the mobile phone portrait mode, but it is handled manually by itself, and the degree of control is higher. There are many such retouching apps, and snapseed is recommended to be better.

The background blur of iPhone portrait mode brings fuzzy effect, the aperture size can be set later, and the depth of field can be controlled at will.

It can be used mainly when shooting people, shielding the messy background, but the background also needs some details. If your subject stands in front of a flat wall, the details will not be blurred, generally about 0.5-2 meters away from the subject.

Small c prompts to open the nine squares and pay attention to the composition: -O

The composition of the subject is very important. When shooting an object, you should first think about the composition in your mind, avoid the background being too chaotic and interfere with the camera algorithm, and try to make the subject stand out ~

You can take a closer shot, of course, not too close, it is impossible to focus. Then focus manually and adjust the exposure.

If you can add a lens, you can also add a lens yourself, such as a macro lens, which can have a more magical photography experience.

The depth of field effect is related to the focal length of the lens. The longer the focal length, the better the filtering effect. The effect of shallow depth of field can also be obtained by installing telephoto additional mirrors and macro lenses. These lenses are definitely better than the ones that come with the mobile phone.

Two ways

Select portrait magic mode in 1, the mobile phone will simulate a more realistic depth of field, and the method is simple.

Keep the subject as close to the lens as possible, such as a few centimeters, so that a natural shallow depth of field appears.

3. Get shallow depth of field in the later stage.

Personally, I don't use iPhone, so I can't demonstrate portrait mode. I photographed demonstrations 2 and 3 with my mobile phone for your reference.

You can pay attention to what you like.

Sorry, I haven't used it.