Photography: Technical parameters of lenses

To determine the optic suit for your best, you should consider the following:
  •     Focal length (or range for zooms);
  •     Luminosity;
  •     Fixed (fixed lens) or a variable focal length (zoom lens);
  •     Manual or automatic focus;
  •     Availability image stabilizer;
  •     Macro ability.

Focal length

Depends on the focal length field of view covered by the lens, and transfer prospects. The smaller (shorter) than the focal length, the greater the angle of view and more pronounced perspective. Lens with a focal length of 50 mm is normal, that is, having a point of view and transfer perspective, similar to the human eye. Such a lens is often used to create natural, realistic-looking pictures.

Lenses with focal length less than 50 mm are considered wide-angle (or short throw). They allow you to fit in a larger portion of the space frame. Stretching the image in the foreground and on the edges, this lens significantly distorts perspective. Most often they are used for landscapes, architecture, and in close quarters.
Separate class wide angle - Lens "fish eye» (fisheye). These lenses usually have an angle of view of 180 degrees on diagonal of the frame. Due to the strong distortion of the prospects of such a characteristic hemispherical lens forms an image. The use of these unique properties, "fish-eye" allows you to create very interesting pictures of architecture, landscape and interior design, as well as cartoon images of people.

Long-focus or telephoto lenses are used for photographing wildlife, sports, and are necessary in cases where you can not come close enough to the subject. A separate type of telephoto optics - portrait lenses. Due to the focal length of 80 to 100 mm, they can get the natural proportions of the human face and blur the background by a minimum depth sharp image space.

Characterized by a minimum value of the diaphragm, which allows you to set the lens. Lens with a large aperture allows the use of shorter excerpts. This means that in low light you get stunningly sharp images. But with decreasing f-number decreases and the depth of field, which is not always the photographer intended. Besides, the price is much higher aperture lenses.

Fixes and zooms

Fixed lenses are almost always superior to zoom lenses for image quality. (Only if you do not compare very cheap fix with a very expensive zoom). In addition, the aperture optics with a variable focal length is not cheap, but affordable high-transmission line fixes have each manufacturer.

Fixes are not so convenient to use, because to solve different tasks, you need a few lenses. Change them in dynamic conditions change difficult. To prefer fixed-lens should, if the speed by changing focal length is not your thing.

Manual and automatic focus

Virtually all modern lenses can the sharpness automatically. But there are lenses and manual focus, especially older models, of which there are specimens with very interesting characteristics. Optics of previous generations can be installed on a modern camera using a special adapter.

Image Stabilizer

Recently, a good practice among manufacturers of lenses and cameras was the installation of the image stabilizer, which allows you to shoot at shutter speeds without a significant loss of sharpness. This is especially true for telephoto shooting, in which to obtain a sharp image requires a very short delay. Modern optical stabilizer allows you to increase the exposure level at 3-4. Some manufacturers have chosen to embed it into the lens; others set the stabilizer into the camera. The presence of the stabilizer in the camera to shoot with a slower shutter speed any lens that it installed. There are lenses, available in two versions - with and without stabilizer. Version without stabilizer usually sharper and about half cheaper.

If you enjoy photography of plants, insects and other objects of small size, it is useful to you macro lens. Due to the maximum magnification and minimum focusing distance this lens produces an image that is close in size to the real.

Cheap macro lens with a focal length of 50 mm and 100 mm are small enough, but to shoot at the maximum of the scale should be removed, almost having rested in the object. This is not very convenient when shooting the same insects. Needed for such shooting macro lens with a longer focal length - 135, 180 mm. They give a greater increase, but more expensive.
Compatibility of lenses and cameras

Unfortunately, most camera manufacturers its own standard lens mounts to the camera. They may be different even in the same manufacturer cameras from different years of release. There is also optics, designed for digital cameras with a matrix that is smaller than a standard frame of 35mm film. These lenses are not suitable for film cameras or cameras with a full matrix. Keep this in mind when choosing a camera and lenses.

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