How big is the difference between Canon red circle lens and ordinary lens in image quality?

The quality of the lens determines the imaging quality! In fact, to be precise, the better the lens, the more stable the imaging level can be under the worse external conditions. That is to say, if it is in a professional studio with good light, you can say that there is almost no difference between the dog head and the red circle (the difference is only the sharpness of the central point), and even the mobile phone is no better than the single contrast! However, we don't have such an ideal studio. Most of the time, it is natural light, etc., and the good lens is reflected. For example, when you shoot on a cloudy day from 18 to 55, the picture is obviously gray, but the L lens won't wait. No one says that the dog's head can't make a good film, but it is accurate to say that the chance of a good film is small ~ ~ Even the master doesn't mean that every shutter is fine ~ ~ There are many factors besides people's technology, and a good film needs the external environment. In fine weather, both heads can produce good films, but people are still better than your imaging.

Let's talk about the differences between the two lenses:

1. The difference between the red circle and the dog's head is that the picture quality is correct, and it is an all-round picture quality, not just zooming in and out. Maybe you didn't notice it because you had less contact. You might as well take one picture of the same angle and all the parameters including the focal length. It's no exaggeration to say that the size of 8*6 can be seen in the size of the camera screen, so it's unrealistic to replace the red circle with a dog's head. In addition, some people below say that the difference is not big, and I don't agree with you. Try it, and you will know

2. The quality is the first factor, and the sharpness of the focus: a good lens can't be too sharp at the point where you are in focus. For example, if I shoot a long-distance object with a short focal length, I can directly take a screenshot of a small-resolution film (such as 8*6) after shooting with a lens with sufficient sharpness. There is little difference between a clear picture and a telephoto shot, and your 18-55 can't do it ~ ~ Too sharp focus will lead to a dry picture, which is hard to describe. In short, you will know after reading the comparison. In the following picture, I took a 7mm bird-shooting screenshot. The proportion of the bird in the picture in the original film: if the whole picture is reduced to 8*6, then the bird is not as big as your fingernail ~ ~ which shows the sharpness and resolution of the picture that 18-55 does not have

3. Color reduction: this is one of the lens elements, which can be achieved through the special lens material and high-level coating. Obviously, there is no sample for the dog head, but you can see it according to the comparison mentioned in my 1. L the color of the lens is closer to the true color of the object ~~

4. Distortion control: If you look at your film carefully, you will find that the photos are actually distorted at the edges, especially at the wide-angle focal length; A good lens actually has smaller focal distortion; You can tell by shooting the same rectangular hexahedron with different lenses at the same focal length from the top view that there is actually a difference between the distorted shapes by computer comparison. Technically, the better the aspherical lens, the better. On the contrary, the 18-55 has no aspherical lens, so the distortion will be greater

5. Jiao Wai control: parents all know that the background number is blurred when shooting with a large aperture, but the blurring and blurring are different ~ the poor lens is blurred and feels shaky. You see that the background blur of some low-end telephoto lenses is large enough, but it is dizzy when you look closely. Good shots don't have this situation ~~

Note that the Jiao Wai in the picture below is actually very moist and solid, and the color won't shake

At the same time, you can know by carefully looking at the sharpness of the focus part in the above two pictures

Let's give you a comparison picture

If this picture is blurred in Jiao Wai, the light spots will not overlap and blur.

6. USM motor: All the red circles are ultrasonic motors, but your head is not. The difference is obvious. You can hear the sound of the motor when you focus, but you can't use the USM head. The help with USM is not only in sound, but also in speed. When the light is enough, the USM motor focuses at least 2~3 times as much as the general motor. That is, if you can focus in one second, you can't use the red circle for the first half of a second. And then there are low light conditions? Generally, the motor can focus many times before it can focus, and the USM will not ~ ~ The weak light has little effect on the USM, but the general motor can't; Furthermore, there is a gap in the accuracy of focusing. There are USM lenses that are rarely out of focus ~ ~ Of course, there are also lenses with ultrasonic motors, but 1% of the lenses with red circles are equipped with ultrasonic motors, so I mention this point

7. Aperture: I don't know if you have noticed that many red circles are constant apertures when the zoom factor is small, and the dog's head is not ~ ~ Constant aperture, for example, 24-7 F2.8 means the maximum aperture regardless of whether it is 24mm or 7 mm. And the maximum aperture of your 18-55 in the 55mm focal length is only F5.6? A large aperture can not only increase the blur effect, but also increase the amount of light entering. In low light environment, it will help to improve the shutter speed ~ ~ Even if these are not mentioned, the unique transparency of a large aperture will be gone ~ < P > 8. Workmanship: the red circle is the L lens, which is almost dust-proof and splash-proof, and your 18-55 is not ventilated on all sides. What's the difference? Hehe, after a few years, your lens will be dusty but L. For example, if you use the camera lens in 18-135 for one year, it will automatically extend when the lens mouth is facing down, but it will not be like this if you use the red ring for five years ~ ~ In addition, if you use the rubber ring with a dog head for three to five years, it will not crack or loosen this L lens ~ < P > 9. Preservation degree: the red ring lens is basically preserved, and it can be sold at a brand-new price of 8-9 fold after three to five years without any damage. Your dog's head can't do this anyway ~ ~ Don't talk about whether it is damaged at that time. It will take more than 5 years to age alone to make this lens worthless ~ ~ What's more, there is no room for upgrading and so on, so no one wants it, so it can't be sold. < P > In fact, there are many differences. Let's simply say these main things. Welcome to ask ~ < P > Please take a closer look at the full text and it won't be worthwhile for me to play for so long.