What does a small telephoto mean in a digital camera

Usually we call a lens with an optical zoom factor of between 3x and 10x as a small telephoto lens, and a lens with a zoom capability of more than 10x as a telephoto lens. The zoom factor is based on 35mm, that is to say, 35mm is equivalent to 1x optical zoom, and 3x optical zoom is 35mm 3=105mm; In the same way, 10x optical zoom is 35mm 10 = 350mm. However, this is only an approximate value, for example, if the wide-angle end of some lenses reaches 28mm, then 28mm 3=84mm, so even if its telephoto end is only 84mm, we can also say that it has 3x optical zoom.

Of course, this value is not absolute, as long as it is roughly in the range of 3x or 10x, we can call them 3x or 10x optical zoom. It should be noted that the 35mm standard** is the same as the 135mm film camera standard, and the size of the 135mm film is fixed at 24mm and 36mm. Because the cost of CCD or CMOS used in digital cameras is much higher than that of film used in film camera imaging, the size is reduced to varying degrees, and then converted to 35mm according to the 135mm film machine.

As a result, 35mm has become one of the most authoritative standards for measuring the type of digital camera lens.

What is a small telephoto used for?

From the above conversion method, we can know that the multiplier is just a ratio. So we can roughly look at it like this, using 100 meters as a benchmark, 3x optical zoom is 100:3, that is, it is about possible to pull an object 100 meters away to 33 meters, so that the object is magnified, and the image quality is basically not affected (except for blur caused by hand shake).

In this way, the role of the small telephoto is more obvious, that is, it can achieve a larger magnification conversion, and objects that are also far away can be pulled closer.

Simply put, it is a digital camera with a high zoom lens (that is, a lens that can zoom in and out over a wide area, from wide angle to telephoto end), and has a DSLR-like form factor.

Specifically, it is actually a small digital camera in the first place, and there is no essential difference between the ** and the small digital camera of the card machine, and the size of the sensor is also the same.

The advantage is that you have a lens that can cover both wide-angle (i.e., large panoramas, close up) and telephoto (telephotographic lenses, i.e., zooming in on things in the distance).

Then, at the telephoto end, you can achieve a certain bokeh effect (i.e., the subject is clear and the background is blurred). Then the grip is much better than that of a regular card machine.

The disadvantage is that it is large in size and somewhat inconvenient to carry.

Small telephoto means a camera with optical zoom within 10x, and most small telephoto cameras are within 7x.

The role of a telephoto lens is as follows:

1. Zoom in on the subject.

When shooting distant objects, using a telephoto lens allows the subject to zoom in and create the feeling of zooming in on the lens. For example, when shooting distant birds, use a long focal length to fill the frame to achieve the effect of zooming in. Sometimes the content of the picture is too cluttered, use the telephoto to zoom in to make the picture concise and remove the content of the picture that we don't want.

2. Compress space.

When we shoot landscapes, the spatial distance between the near and far shots is far apart, and the use of a telephoto lens can shorten the spatial distance between the long and close shots, and the distant scenes in front and back can be shot with a compact picture effect.

3. Background blur.

The longer the focal length, the farther away the subject from the background, and the depth of field.

The shallower it is, the higher the degree of bokeh will be. It is suitable for shooting people, animals, etc.

Precautions for the use of telephoto lenses

1. Due to the long focal length, the camera is prone to shaking, use a tripod and remote shutter to reduce unnecessary shaking.

2. Pay attention to the depth of field, using extreme focal lengths at such close distances can reduce the depth of field to a fraction of a millimeter. Make sure the subject is clear, use a small enough aperture to ensure that the depth of field extends over the entire subject.

3. If you want to capture your subject from front to back, keep it parallel to the sensor. At extreme focal lengths, the depth of field will be so narrow that there may not be more than a few millimeters of depth of field to use.

4. If the telephoto lens has an AF MF switch, switch it to manual focus.

and manually frame the focus of the shot. You may notice that the minimum focusing distance decreases when focusing manually. This means that the subject can be brought closer to the subject, resulting in higher magnification.

5. Use a teleconverter to increase the focal length while maintaining the same minimum focusing distance. This can significantly increase the magnification of the subject without having to move farther.

A wide-angle lens means a photographic lens with a shorter focal length than a standard lens, a larger angle of view than a standard lens, a focal length longer than a fisheye lens, and a smaller angle of view than a fisheye lens.

A telephoto lens means a photographic lens that is longer than the focal length of a standard lens. Telephoto lenses have a long focal length and a small angle of view, and large imaging on the negative. As a result, larger images can be captured at the same distance than standard lenses.

A wide-angle lens is a photographic lens with a focal length shorter than a standard lens, a larger angle of view than a standard lens, a longer distance than a fisheye lens, and a smaller angle of view than a fisheye lens. Wide-angle lenses are divided into two types: ordinary wide-angle lenses and ultra-wide-angle lenses. 135 cameras The focal length of an ordinary wide-angle lens is generally 38 24 mm, and the angle of view is 60 84 degrees; The ultra-wide-angle lens has a focal length of 20 13 mm and a viewing angle of 94-118 degrees.

Due to the short focal length and large angle of view of the wide-angle lens, it is possible to capture a large area of scenery in a short shooting distance.

A telephoto lens is a photographic lens that is longer than the focal length of a standard lens, with an angle of view within 20 degrees and a focal length of tens or hundreds of millimeters. Long focal length lenses are divided into two categories: ordinary telephoto lenses and super telephoto lenses. The focal length of a normal telephoto lens is close to that of a standard lens, while the focal length of a super-telephoto lens is much larger than that of a standard lens.

Taking the 135 camera as an example, the photographic lens with a focal length of 85 mm to 300 mm is an ordinary telephoto lens, and the one with a focal length of more than 300 mm is a super telephoto lens.

(The camera takes a clear picture).

The imaging quality of a digital camera, in addition to the factor of lens quality, largely depends on the pixel level of the imaging sensor.

The higher the number of pixels, the higher the pixel level, the higher the resolution of the image, and the more the image is captured.

Delicate, clear,

Hierarchical .

The pixel level of low-end digital cameras is generally low, with only hundreds of thousands of pixels;

The pixel level of mid-to-high-end digital cameras is relatively high, and most of the pixels are above 10 million.

The higher the pixel level and resolution.

The higher the grade and price of the camera, the better the image quality.

Digital Camera : Optical Zoom.

Optical zoom is called optical zoom in English, and digital cameras rely on an optical lens structure to achieve zoom.

The optical zoom method of a digital camera is similar to that of a traditional 35mm camera, that is, the lens movement is used to zoom in and out of the scene to be photographed, and the larger the optical zoom factor, the farther the scene can be captured.

When buying a digital camera, many users ask.

What is digital zoom and what is optical zoom.

Optical zoom is created by a change in the position of the lens, object, and focal point.

When the imaging surface moves horizontally, the vision and focal length change, and the farther scenery becomes clearer, giving the impression that the object is progressing.

Obviously, there must be two ways to change the angle of view, one is to change the focal length of the lens.

In photographic parlance, this is optical zoom.

The focal length of the lens is changed by changing the relative position of the lenses in the zoom lens.

The other is to change the size of the imaging surface, that is, the diagonal length of the imaging surfaceIn the current digital photography, this is called digital zoom. In fact, digital zoom does not change the focal length of the lens, but only changes the angle of view by changing the angle of the image facing the diagonal, thus creating an effect that is "equivalent to" the focal length of the lens.

So we see that some digital cameras with longer lenses have more room to move the lenses and sensors inside, so the zoom factor is also larger.

We see that some ultra-thin digital cameras on the market generally do not have optical zoom function, because the inner root of their body does not allow the movement of the image sensor, and like Sony F828,

Fujifilm S7000 these.

Long lens" digital camera with optical zoom capability up to 24x.

A wide angle is a wider shot.

Telephoto is to shoot farther.

The reward score is so high, wait for me to find the answer for you.

The main feature of the telephoto camera is actually different from the principle of the telescope, and the focal length is changed by the movement of the lens inside the lens.

When we shoot distant objects or when the subject does not want to be disturbed, the benefits of telephoto come into play. In addition, the longer the focal length, the shallower the depth of field, and the larger the aperture, the shallower depth of field effect is the same, the advantage of shallow depth of field is to highlight the subject and blur the background, I believe that many fans are rotten orange when taking pictures to pursue a shallow depth of field effect, so as to make the shooting more professional.

Introduction: The most basic feature of the medium and telephoto lens is that the lens angle of view is small, so the field of view is relatively narrow; It can bring the distant scenery closer and fill the picture, and has the function of "looking far away", so that the sense of distance and proximity of the scenery disappears; The depth of field is shortened, and the sharp range before and after the subject's focus point is limited to a certain scale, so as to highlight the part in focus (mostly the subject or the part to be highlighted). The angle of view is small and the field of view is narrow.

Basic performance

Due to the lens's small angle of view and narrow field of view, a mid-telephoto lens represents only a small or even small part of the exterior that the human eye normally observes. Photographers may have the experience that when a telephoto lens is attached to the camera and observed from the viewfinder of a single-lens reflex camera, it is impossible to imagine the direction of the scene that fills the viewfinder for a while, so they have to take their eyes off the camera finder eyepiece to look at the real scene, so as to realize that the lens field of view is too narrow, and what it "sees" is only a very small part of the picture that the human eye usually sees, and the lens magnifies this rather small part and fills the picture.

By taking advantage of the small field of view of the medium and telephoto lenses, photographers can make subtle portrayals of the subject's performance when shooting close-ups, and highlight a beautiful part of the scene when shooting landscapes. The small angle of view and narrow field of view of the telephoto lens also make it easy to bring together the scenery in the composition, so that the picture is relatively compact. When the focal length of the lens used is long and the focus distance of the subject is very close, the focused target will be placed very large, resulting in a peculiar effect.

It can create a sense of compression in the front and rear subjects. Another significant effect of a mid-telephoto lens is to "pull in" distant subjects to the fore and fore as if they were compressed. In some major sporting events, groups of photojournalists often set up cannon-like telephoto lenses to shoot the overlapping scenes of athletes at the start of the marathon, because in this case, the photographer relies on the telephoto lens to aim away from the subject, which can "close" the athletes in the distance, and at the same time bring the effect of compressing the front and rear scenes, presenting an atmosphere of urgency on the picture with the tail of the subject chasing closely.

The focal length is long and the depth of field is short. Photographers can often see some short depth of field effect**, these ** pictures are contrasting with reality and virtuality, the main subject is clear and the secondary subject is blurred, which has a strong artistic appeal. The vast majority of these short depth-of-field effects are shot with a telephoto lens.

Telephoto lenses have the property of shortening the depth of field of the subject. In particular, when a telephoto lens is used in conjunction with a wide aperture and short shooting distance, it has a particularly obvious effect on shortening the sharp range before and after the subject, and this technique is often used in photography of portraits and other subjects.