The telephoto lens is a great tool that allows you to get great shots where other lenses are simply powerless. What are its features, advantages and disadvantages? Let's get it right.
What it is?
A telephoto lens is a device for the camera, the focal length of which significantly exceeds the diagonal of the frame. In this case, the angle of the field of view can be from 10 ° to 39 °. The purpose of lenses with such a focal length is to photograph distant objects, because they can significantly zoom in on the subject and significantly increase the image. They are indispensable if the photographer does not have the opportunity to come close to the subject, and you need to take a photo on a large scale, focus on a small nuance or close-up.
The increase in the subject will be more noticeable, the greater the difference between the focal length parameters of the standard and telephoto lenses, and the perspective of the photograph will seem more compressed. That is, the distance to distant objects will seem much less.
What are they used for?
Shooting with a telephoto lens is indispensable in hunting for large and small animals. Another area of application of such a device is portrait shooting, however, it has its own characteristics. So that the proportions of the face are not distorted in the photo, the photographer needs to shoot from a sufficiently large distance (1.5-2 m). Wide-angle and standard lenses when shooting from this distance give a small image.
First feature
What are the features of telephoto optics?
Firstly, it enlarges the image. For example, optics with a focal length parameter of two hundred millimeters will almost four times exceed the focal length of a standard lens (50 mm). Accordingly, the image scale will be four times larger. It follows that the magnification can be found by dividing the focal length by 50. For example, the MTO-1000A Soviet long-focus lens has a focal length of almost 1100 mm, respectively, the magnification is 22.
The possibility of a significant approximation of the subject is one of the most valuable properties of such lenses for photographers, because this is the only way to make beautiful shots of wild fauna or any other objects that cannot be approached for any reason.
However, one of the main drawbacks of such optics also follows from this - size. "Powerful" lenses with a large magnification are heavy and bulky, they are almost impossible to use in the absence of good support. She most often serves as a tripod.
Another negative feature that should be taken into account is that the telephoto lens makes all the disadvantages caused by the quality of the lens itself and the vibrations of the camera noticeable. It is almost impossible to avoid with the heavy weight of the device. Because of this, many telephoto lenses cannot compare with conventional lenses in terms of sharpness, but they are much more expensive than the latter.
Second feature
Another important feature of telephoto optics, for which photographers love it so much, is the ability to highlight the subject against the background, that is, beautiful blur. This is very useful if, for example, the animal stands on the background of vegetation. What makes a strong background blur? The fact is that the telephoto lens has a small angle of view (for example, for a device with a focal length of 400 mm, this is only 5 °), and the depth of field is less than that of standard samples. Thus, if the aperture is fully open, the depth of field is a narrow strip, so all the space except the object itself is in focus.
Third feature
There is another feature that is also associated with a shallow depth of field. It is of particular importance when photographing fauna. Objects, both rear and front, will be out of focus and will be blurry. This means that various thin vegetation, which will be clearly visible in the photo from a standard lens, will be practically invisible in the photo from telephoto optics.
Aberration
Aberrations are called deviations of the photo from the norm. In the case of telephoto lenses, we are talking about a specific type of aberration - distortion, that is, curvature of geometry. This means that the scale of the photo will change from the center to the edges. Straight lines can become convex or tend to the edges of the photograph, in which case this is the so-called barrel-shaped distortion. If the lines become concave and tend toward the center, then this is a cushion-like distortion.
In some cases, chromatic aberration may occur, which manifests itself as an effect of the color outline of the object. This can be eliminated after shooting, using graphic editors. The process will be easier if the photographer shoots in RAW format.
Shooting genres
Let us dwell in more detail on the use of telephoto lenses.
- Sporting events. In such cases, photographers are usually prevented by fences, and the distance to the subject is large enough. “Televik” in this case is simply irreplaceable, however, it is worth remembering that the image is easy to “lubricate”, so the shutter speed must be set to 1/1000 seconds and use a monopod or tripod.
- Architecture. To consider and capture all the details of a particular architectural building is not a problem if there is a telephoto lens. If with a standard lens from a far distance only the general plan can be removed, then the “telephoto” will highlight the part of interest.
- Landscapes. Standard lenses can be uncomfortable in landscape photography, because they give too general a plan. The telephoto lens will “take” the peak of the mountain, a seething waterfall and any other objects that are at a sufficient distance.
For Nikon
An example of a popular Nikon telephoto lens is the Nikon 70-200mm f / 4G ED VR AF-S. Photographers call it one of the best lenses in many ways, which, however, does not include price. At the moment, its minimum threshold is 90 thousand rubles.
This is an excellent telephoto lens with a constant aperture, the parameter of which is 4. Its huge plus is image sharpness. That is, the frames made by him are not inferior in sharpness to standard lenses with similar parameters. Compared with the "brothers" has a small weight, and few representatives of this type of optics can boast of this. There is an excellent image stabilizer, and the focus is quiet.
More budget option - Nikon 70-200 mm f / 2.8G ED-IF AF-S VR.
For Canon
An example of a Canon telephoto lens is primarily the Canon EF 70-200 mm f / 2.8L IS II USM. This telephoto lens is very heavy, its weight is 1.5 kg, which greatly affects the physical condition of the photographer during prolonged shooting. It does not fit in every bag, so you have to either pick it up specifically, or carry the camera in your hands or on your neck.
The lower cost threshold at the moment is 125 thousand rubles.
This high-quality optics has two modes of operation of the stabilizer, almost silent and very fast autofocus. Its protection is quite high, so the photographer has the opportunity to take photos in bad weather conditions, such as snow and rain. There are chromatic aberrations in the photo, but they are at a low level, but vignetting will appear on the open aperture, which can slightly ruin the frame. Canon comes with a tripod leg for this telephoto lens.