The zoom problem of the SLR lens, can the SLR lens zoom automatically

In order to drive the focus and zoom of a DSLR lens, a mechanical motor structure with strong torque is required

Zoom aside, Nikon's focus motor is difficult to drive for some "huge" lenses, and the torque required for zoom in a DSLR lens far exceeds the torque required for focusing.

And for the cost issue, I just said, if you want to add a zoom motor, it will be designed inside the lens rather than the body, assuming that there will really be a "zoom motor", its torque will be stronger than the "focus motor", and the silent design will be more cumbersome, if you really want to design such a motor in the lens, then its cost will be much higher than the current "ultrasonic motor" or "quiet motor", cheap lenses don't need to mind....But for the "spear cannon", the addition of such a motor will cost much more.

Then there is the problem of contacts, if you do add a "zoom motor", then all existing cameras will not be able to drive this function, if you want to experience this future "zoom motor", then you even need to buy a DSLR body with new contacts.

So don't think about it....Besides, twisting the zoom ring isn't really that different from a push-button zoom, is it?

It can only be twisted, and in actual use, twisting the zoom ring to zoom is easier to operate and convenient. There are many things like this kind of function that are only for selling points and not practical in the guochan brand.

Can the SLR lens zoom be operated with the body? You're too imaginative, but I don't know if a top-of-the-line internal zoom lens can be achieved, but the 18 55 is definitely not going to work.

If there's another way, it's a duplication of functionality, and if it's designed, then that product is a failure.

Only by changing the focus ring, the fuselage operation can only be done by the card machine, and the mirrorless SLR can not change the lens.

In fact, there are, but there are almost no new products now, so there are very few such products on the market, if you are interested, you can try Nikon, Pentax, Sigma and other brands of old lenses, many are zoom manual focus lenses.

Nowadays, there are very few zoom lenses that can be manually focused, and the main reason is that when using a zoom lens to manually focus and shoot, the actual operation is more complicated, so it is not very practical. If you often use manual focus lenses, you should be able to understand that if you are very familiar with a lens or even a specific focal length, you can estimate the focus before shooting, and screw the focus ring to the roughly appropriate position in advance, so that you can ensure accurate focusing as long as you fine-tune when shooting, and the actual shooting efficiency is very high, and in some cases even higher than autofocus. However, if you use a zoom lens, you are likely to adjust the focal length again during the shooting process, and the focal length adjustment is often limited by the structural design of the lens, and you have to refocus, so the shooting efficiency is much lower than that of an autofocus lens.

In addition, the structure of the zoom lens is relatively complex, and even if the autofocus motor structure is removed, the volume and weight are often not well controlled. As I said above, this problem actually does not exist in cinema lenses, but the volume and weight of zoom cinema lenses are definitely beyond the reach of ordinary photography enthusiasts.

1. The single-lens reflex mirror cannot automatically zoom.

2. The reasons are:

3. First, the zoom process is the process of photographic composition, which also requires more accurate adjustments. Auto-zoom tends to be uncontrollable and can control the range and angle at will.

4. Second, auto-zoom consumes a lot of power. Compared to non-SLR long zoom heads, SLR lenses have a larger lens aperture and a larger optical zoom ratio. Therefore, it is not easy to autozoom from the perspective of power saving.

5. Third, a SLR lens is a lens that can be converted. In order to achieve autofocus, it is necessary to add a corresponding drive motor to the lens, which not only increases the cost of changing the lens, but also spends a lot of effort on data transmission with the camera, which is of little significance. For photographers, it will not be because of the automatic zoom, which will make the best quality improved, more convenient shooting, and lower cost.

Here's how to use the zoom lens:

1. Lens operation: change the focal length by pushing and pulling the lens back and forth, and rotate left and right to focus;

2. Correct focusing: focus with a long focal length first, and then choose the appropriate focal length to shoot;

3. Choose a lens hood: If the lens hood is not selected properly, the shading will not be visible on the viewfinder screen of the single-lens reflex camera, but it will be displayed on the film;

4. Control the depth of the picture: shoot with a focal length of 60 mm at a distance from the subject, and shoot with a focal length of 300 mm at a distance from the subject.

1.There is no number change in SLR. Changing numbers is garbage. The main parameter for long-distance shooting is the focal length. For example, with a focal length of 500mm, you can zoom in on the entire frame from a distance of 50-60 meters. The longer the focal length, the higher the magnification, the higher the **.

This means that the lens zoom range from 18mm to 55mm, 55 18 = 3x. If the lens parameter is only 1 value, for example, 100mm, it means that you can't zoom, which means that you can only run forward if you want to zoom in. A lens that cannot be zoomed is called a prime head.

3。In fact, no one on the SLR cares about the zoom factor, the photographer cares about the actual focal range. For example, the 18-55 is suitable for wide-angle to average shooting.

24-70 is suitable for most travel shooting, and the general understanding is that people who can shoot near can also shoot distant scenes. The 70-200 is suitable for medium-to-long distance shooting. Above 300mm, there is generally no zoom.

People care about the actual distance of the shot, not the zoom factor.

In addition, it should be known that the imaging quality of fixed focal length lenses is generally better than that of zoom lenses; The greater the zoom amplitude, the worse the image quality and the more difficult it is to use.

1. It mainly depends on the lens, and it has little to do with the fuselage.

2. I don't understand what it means, SLR wood has digital zoom, how much focal length of the lens, is how much zoom, 18-55 is 55 18 = 3 times light change.

3. It is a telephoto lens, mainly the focal length and the maximum aperture. In terms of structure, it depends on the aspherical lenses and UD lenses used.

The zoom of a DSLR lens is the telephoto end divided by the wide-angle end.

1.In order to shoot close-ups at a long distance, the focus is mainly on the focal length at a long distance, and the effect is based on the aperture and shutter (such as the degree of bokeh). When shooting close-ups in the telephoto segment, the background is blurred and the subject is highlighted, so it is best to use a lens with a constant aperture.

2.The 18mm-55mm of the full body corresponds to the DX format body, and the focal length angle of 50mm is about the same as the angle of view of the human eye, so the 50mm lens is also called a standard lens, referred to as the header. The smaller the focal length, the greater the viewing angle. Vice versa.

3.What you're looking at should be a telephoto lens. Lens parameters are one thing, I personally think it depends on the material of the lens, look at the lens has a few ED lenses, a few aspherical lenses, simply put, the more these two lenses, the better.

There are probably several telephoto lenses on the market, such as prime lenses.

It must be optical zoom, digital zoom means how much you can zoom in on the camera after you shoot **. The typical zoom range of a mid-range SLR is 18-105mmBut it also depends on what brand of camera and lens.

1. Light change.

2. The entry SLR is the APS-C format, which is about the conversion factor. For example, 18*, the wide-angle end is 27mm

3, of course, the focal length is long, you don't need to look at the magnification, just look at the focal length of the telephoto end, such as 55-180, 55-270

It's to install a telescope if it doesn't work, it's cheap and can hit birds, but it has some impact on the picture quality.

1. In addition to shooting far, the telephoto end also has a magnifying effect on the distant scene (the same scene, shoot with 100mm and 50mm, and magnify twice with 100mm), because the telephoto is usually far away, it will also compress the distance between objects (reduce the three-dimensional sense of the scene) and reduce the size contrast between the scenes (perspective disambiguation).

2. The wide angle can accommodate more scenes, and the amount of light entering the wide angle is more than that of the telephoto under the same aperture, that is, the aperture is larger (except for the high-end constant aperture zoom head on some SLRs, most lenses have a larger aperture at the wide-angle end than at the telephoto end), and at the same time, the wide-angle end is generally used to focus in a relatively close place, the distance between the near and far shots is expanded, and the contrast between the size of the near and far shots is also more obvious (perspective disambiguation), which is suitable for more exaggerated expression techniques. Panorama mode is spliced together with multiple **, which will lose a certain number of pixels (become slender strips), and it is best to use a tripod to shoot, and it is not easy to deal with the scenes of people coming and going (especially the seams), and the wide angle is much easier.

3. Generally more commonly used focal length (converted to 135 camera):

28mm and below: Landscape.

35-60mm: Take a trip here.

85-135mm: Portrait.

Above 140mm: Photograph birds, wild animals or scenes that are not easy to get close to.

Generally, the home usage rate above 140mm is relatively low, and it is not easy to shoot steadily when shooting handheld.

The principle of optical zoom is to change the size of an image by changing the size of the focal length. Inside the optical zoom camera lens, there are lenses that can be moved. The image sensor behind the camera is fixed, and when the lens moves, the focus is moving.

As the focus shifts, the distance to the sensor behind changes and the focal length changes. When the focal length changes, the size of the image changes. So it can be explained in unprofessional but relatively easy to understand words, that optical zoom only changes the distance at which the light travels, and the light itself does not change.

It's like a person, there is no change after walking a thousand meters and walking two kilometers. (Although walking more can **, but here we will ignore the fat burned for the first kilometer for the time being!) Light also attenuates as it travels farther distances, but camera lenses are generally short, so let's ignore this attenuation for now) Since the light does not change, the image presented after the focal length changes also does not change.

Therefore, the biggest feature of optical zoom is that the pixels of the image will not change after magnification, that is, the picture will not be affected.

In fact, the most basic principle of digital zoom is to carry out a fixed ** method. If you still don't understand, then take out your phone, click on a **, and then zoom in and ....... This magnification process is called digital zoom.

What do you think? What technicians want to do with their heads, you can do it with your hands, is there a sense of accomplishment! When you put it very large, the whole screen may only be able to see a part of the original **.

This part will become more and more blurry as you zoom in. Because digital ** is composed of pixels, it can be seen as composed of small dots or small squares. There is a gap between these blocks.

In the original **, this spacing is too small for us to detect with the naked eye, so the whole picture looks relatively beautiful. However, as it gradually zooms in, the spacing between pixels and the pixels are also enlarged. This not only looks blurry, but also very stiff to the naked eye.

So digital zoom will damage the image quality. In the process of practical application, the digital zoom process of the camera will have corresponding algorithms to make up for this shortcoming. Usually, at the same time as the digital zoom, the "gaps" between these pixels are filled by technical means.

After all, the effect of filling it up through software is not as good as the real one. The change of light and shade of color, the variety of color and luster, cannot be calculated. Therefore, after the digital zoom is magnified, although the software can make the ** less blunt, it will inevitably lose details.