The large aperture lens of a SLR is as big as a fist, and the lens of a mobile phone is only as big as a soybean. Why dare you call it F 1.8?

The lens of the mobile phone is so small that the aperture F 1.8 is not fake. The definition formula of aperture is aperture = focal length. The focal length is the distance from the center of the lens to the sensor. The thickness of the mobile phone is very thin, about 8 mm. If the occupation of the lens, the thickness of the sensor and the back cover of the mobile phone are removed, the distance between the lens and the sensor is very small, about 3 ~ 4 mm, so the aperture of the lens is less than 2mm, but it is very large. Its function is the same as that of SLR. Some people say that SLR can take good photos in dark light, but mobile phones can't, and it is suspected that the aperture is not true. The problem is not the aperture, but the sensor. Suppose the cell phone sensor 1/2.5 area is less than 23.6mm? If the pixel is1.2000, then the area of each pixel is 1.96um? . If the SLR is half width, the sensor area is 432mm? There are 24 million pixels, and the area of each pixel is 18um? The pixel area of mobile phone is 0. 1 1 of SLR. Pixels are photosensitive cells, and the pixel area determines the image quality. Through the above analysis, the picture quality of the mobile phone in dark light is definitely much better than that in single contrast, and the noise is obvious. The number of mobile phone pixels has increased to 20 million, and the situation is even worse. Moreover, because the focal length of the mobile phone is too small, the increase of the sensor area will lead to the corner darkening and the edge blurring, and this situation will continue. Although the aperture is not small, the background blur is very bad because the focal length is short and the depth of field is too long.

There is no doubt that the answers of experts and masters are correct, but my math and physics are not good enough to understand those foreign codes and formulas. Let's talk intuitively: you take a button and see a buttonhole on it, which is about the size of a mobile phone lens. From a distance, is the buttonhole small, but from the front, it feels great, with plenty of light and clear scenery.

In this way, your eyes are like photosensitive chips, and the lens of your mobile phone is equivalent to watching buttonholes at close range! Is it not 1.8? Is it 16?

If you think it makes sense, please give me a compliment, thank you!

Aperture is not an absolute value, but a relative value of focal length/aperture, so the F 1.8 on the mobile phone is much smaller than that of the SLR, which does not mean that the aperture value of the mobile phone is fake. Strictly speaking, a mobile phone lens with an aperture of 1.8 and a SLR lens with an aperture of 1.8 need the same shutter speed to obtain the same exposure value, but the same aperture is different. Mobile phones are limited by the size of sensors. At the same focal length, the aperture of mobile phone F 1.8 is similar to the depth of field of full-frame SLR F 1 1.

Bull's eyes and cat's eyes can be completely opened or narrowed, regardless of size.

This question is asked to confuse the difference between the aperture value of an optical lens and the actual aperture size, which is not the same thing. Aperture value is the ratio of lens focal length to aperture diameter. Don't say that the lens of a SLR camera is as big as 1.8 aperture. If the phone lens is so small, there should be no 1.8 aperture. The focal length of mobile phone lens is also very small compared with SLR lens. That's why.

According to the focal length and luminous flux, a relative value problem is calculated by formula. No matter how big the aperture of a mobile phone is, the picture quality is not as good as that of a SLR. This is determined by congenital conditions. Like sparrows and ostriches. Although they are all birds, they are completely different in size.

Lens aperture and aperture are not the same concept. It is the grating that determines the aperture size. The same aperture, the larger the aperture, the greater the amount of light, no problem. But the same aperture, the larger the aperture, the greater the amount of light. Therefore, the amount of light entering is determined by the aperture and the aperture, not a single factor. Therefore, because the lens aperture of the mobile phone is too small, even with a large aperture, the photographing effect is far better than a single contrast. Those advertising mobile phones are better than SLR, and they are all bragging. It's just that the aperture and sensor size determine that the mobile phone can't take better photos than the SLR.

The algorithm of aperture is to divide the focal length by the maximum incident aperture. Although the focal length of the mobile phone is marked as the equivalent focal length of 28mm, the actual focal length is usually around 8mm, and the aperture of the mobile phone lens is about 4 to 5 mm. It is not surprising that the aperture marked as 1.8 is an opportunistic practice of mobile phone manufacturers, just like the memory card of 16G only has 14g.

The F 1.8 of video mobile phone is used by mobile phone, unlike the F 1.8 of SLR, which is not comparable. Both of them have different aperture materials and process treatment. The aperture of mobile phone is mostly realized by virtual algorithm, so we don't need to delve into this professional place, which is the work of other engineers ... After all, it is convenient and simple to share mobile phone photos, and the imaging quality can be improved year by year.

This video focuses on the function, effect and usage scene of our mobile phone's large aperture in 2 minutes. Especially friends who like to take portraits and delicious food, don't miss it! Simple and straightforward, I hope I can help you. Welcome friends who like mobile photography to watch and pay attention to this number! Click on the text to watch the video.

The reason why I ask this question is that you haven't fully understood the concept of aperture f value. The f value of the lens does not represent the absolute size of the lens opening, but only represents the ratio of the focal length of the lens to the diameter of the entrance. This is a relative figure. Take a 50/f2 lens as an example: if the aperture of the lens is opened to the maximum and the light passing diameter is 25mm, then the maximum aperture of the lens is f2=50/25. Simulate the mobile phone lens again: (It's not measured, it counts) If the focal length of the mobile phone lens is only 5mm and the maximum luminous diameter is only 2.5mm, then 5/2.5=f2. Then the light density projected by these two lenses onto the negative sensor is equivalent and the same. So the size of the aperture depends on the ratio of focal length to diameter, not just the absolute size of the aperture.