What types of lenses for SLR cameras are there? How to choose a lens: from complex to simple and vice versa

(State Prize, 1941) More than 60 years have passed. And his cause lives on and wins. The legendary MTO was replaced by RUBINAR, produced by .

MTO lenses were characterized by tight alignment tolerances. RUBINAR lenses have a similar optical scheme, and some changes have been made to the design: earlier the mirror was applied to the reverse side of the front meniscus lens, now it is mounted on a “cork” in a hole in the center of the meniscus. Although the tolerances probably remained the same, however, changes in manufacturing technology made it possible to obtain a lens with a resolution of 50 line pairs / mm, which is 10 lines / mm more than the MTO or ZM - 5 SA, and at a very moderate price (about $ 100 ).

The lens we are considering consists of three main components: an afocal meniscus that keeps the outgoing beam parallel to the incoming one and is convenient for eliminating spherical aberration; a mirror system and a compensator that corrects the coma and curvature of the image surface. The lenses are well corrected for chromatic aberration. Focusing of mirror-lens objectives is carried out by moving the meniscus with the mirror fixed on it relative to the fixed mirror and the glued lens. This method of focusing allows you to move from infinity to short distances when shooting with very small movements of the meniscus.

The main application of such systems is astronomy. The world's largest Maksutov telescopes (meniscus diameter 70 cm) are installed at the Abastumani Astrophysical Observatory (Georgia) and at the Cerro Roble Observatory (Chile). However, reflex lenses have proven themselves well in photography. Below, I will try to show the capabilities of the MC RUBINAR 8/500 using several examples when working together with a Canon EOS D60 and Casio QV4000 digital camera.

A feature of reflex lenses is that they have one fixed aperture. Compared to lens objectives with the same aperture, these objectives have larger diameters. Neutral density filters of different density are used to adjust the luminous flux. The lens in question is supplied with a neutral filter H-4x (thread 77 × 0.75) and an orange O-2.8x, a hood is also included in the kit. There are also faster reflex lenses, but this one is remarkable in that its thickness does not conflict with the protrusion on the camera body, in which the flash is hidden. A lens with an M42 thread took part in the testing (lenses with a K mount are also available). The lens was attached to the Canon EOS D60 using an adapter ring from the company. As the shooting of the worlds showed, the lens has practically no chromatic aberrations. The resolution is also beyond praise and is probably limited by the matrix in this system. However, a large light scattering coefficient is observed, resulting in reduced image contrast. However, given the 16-bit representation of the image in the Canon camera and the possibility of subsequent editing, this disadvantage cannot be considered very significant.

The angular field of the lens is about 5 degrees for a 24×36 mm frame. Given that the sensor is smaller than film, an image captured with this lens on a digital camera will look like it was captured with a lens with a focal length of 750 mm on film. If you add a TK-2 or TKL-2 teleconverter to the optical system, then the angle of view will correspond to lenses with a focal length of 1500 mm for cameras designed for 35 mm film. Optical scheme of teleconverter TK-2

With such an optical system, the diameter of the moon in the image will be 1150 pixels. The article shows a picture of the moon taken without a teleconverter, but a picture taken with a TK-2 teleconverter (manufactured by the Kharkov Precision Instrumentation Plant) can be viewed (83 KB).

A camera with this lens is a good photo gun, although, of course, you can’t shoot birds in flight. The device must be mounted on a tripod, and in order to achieve acceptable sharpness, focusing must be very accurate. As the calculation of the depth of field () shows, with a distance to the object of 10 m, the depth of the sharply depicted space will be only 10 cm.
Reduced fragment; To see the whole frame, click on the photo with the mouse. The file size is 267 KB.

Birds in flight have to be clicked with significantly shorter focus optics, but autofocus allows you to get a sharp image in that short moment when the seagull is directly above you. The above photo was taken with a Soligor lens with a focal length of 210 mm. Given, though large, but a miniature of the frame; the whole frame can be seen by clicking on it with the mouse.

Canon D60 + Soligor - 2.8/210
Reduced fragment; To see the whole frame, click on the photo with the mouse. File size 65 KB.

With such a small depth of field, a significant part of the frame may turn out to be unsharp. Quite a lot of attention has been paid to the issue of image sharpness recently, even the special term Bo-Kyo has appeared. It is assumed that sometimes the unsharp part of the image can spoil the impression of even an outstanding plot. It is considered that "good unsharpness" is one where the energy diagrams of the stray spots of the optical system have a high peak in the center, fading evenly towards the edges of the spot. Due to the optical design of a mirror-lens objective, the energy diagram of the scattering spot has a decline in the center. Therefore, unsharp point light sources will be displayed as rings. Unsharp thin lines will split in two. In the general case, this is, of course, a drawback. But sometimes the image turns out to be somewhat unexpected and quite pleasant.

By adding an eyepiece to the lens, we can use it as a telescope or, as was shown in the article “Kepler Tube”, shoot with it with cameras that have fixed lenses.

The following illustrations show a fragment of a frame depicting a stump, taken from one point by a Casio QV4000 camera with a telescopic system consisting of Helios 44 and MC Rubinar-8/500 lenses; Canon D60 camera with MC Rubinar 8/500 lens; and Canon D60 camera with TK-2 teleconverter and MC Rubinar 8/500 lens.
Casio QV4000+ Helios 44 + MS RUBINAR - 8/500 (detail)

Lenses.
This article is about lenses. It is necessary to immediately make a reservation that it is designed mainly for those who are not very versed in technical features and terms. For this reason, some of the information will be omitted, and the main part will be presented as simply as possible.

Why are lenses needed?

Probably, everyone who has just purchased or is about to purchase a SLR camera wondered: why, in fact, such a variety of lenses is needed if a lens (the so-called “whale lens”) is already supplied with the camera. For normal everyday tasks, such a lens is likely to be sufficient. However, there is an opinion that the more expensive and better the lens, the better it shoots, and this is true, but it must be borne in mind that it is not the equipment that takes pictures, but the person. The lens is just a tool that gives great opportunities, and with the right selection it will allow you to get the characteristics you personally lack.
Thus, first of all, you need to decide for what purposes the lens is required, since there are not only universal lenses suitable for many tasks, but also very specific lenses, for example, telephoto lenses or tilt-shift lenses.

So what is a lens? Wikipedia says: lens - an optical device designed to create a real optical image. In optics, it is considered equivalent to a converging lens, although it may have a different look, for example, a "Camera Obscura". Usually the lens consists of a set of lenses (in some lenses - from mirrors), designed for mutual compensation of aberrations and assembled into a single system inside the frame. Simply put, this is a system of lenses in a frame that focuses the image on the sensitive element of the camera (film or matrix).
Today, there are a huge number of different lenses on the market in a wide price range, they are produced by different companies and have different characteristics. Each camera manufacturer (eg Canon, Nikon, etc.) produces "lenses" for their devices, which have their own lens connector - the so-called "bayonet". In addition, there are third-party companies that produce lenses for different brands of cameras. The most famous of them are Sigma and Tamron, less common lenses are Tokina, Samyang, etc. When choosing, you should specify whether the lens works stably with your camera and it is advisable to check the lens before buying. However, when choosing a lens, the manufacturer is far from the main thing that you should pay attention to. Much more important are the characteristics, which will be discussed later.

Lens Specifications

The main characteristics of the lenses are as follows:
Focal length (and the possibility of changing it);
Lens field of view angle;
Aperture;
Maximum relative aperture (sometimes incorrectly called aperture ratio);
Bayonet type or camera thread diameter - for interchangeable photographic or film lenses.
In addition to them, there are some additional characteristics (different types of aberration, resolution, etc.), which we will not touch on.

Lens focal length
The job of the lens is to form an image on the sensitive element (film or matrix) of the camera. As is known from the school physics course, the focal length is the distance from the center of the lens to the focus (the point of intersection of the rays or their continuation, refracted by the collecting / scattering system).

The lens is a collecting system of this kind, which focuses the light entering it on the matrix. The focal length of the lens is the distance from the optical center of the system to the sensing element.

If we forget about the theory and put it simply, then the focal length of the lens characterizes the ability of the lens to bring objects closer. In order not to get confused, you can remember a simple formula: the larger the focal length, the closer the subject will be. The following are photos taken from the same position, but using lenses with different focal lengths:

A visual representation of the principle of operation of the simplest lens:

Focal length is measured in millimeters. As a rule, its value is indicated on the lens itself.

Nikon AF-S DX Nikkor 55-300 mm lens
Code: 130335

Lens Sony SAL-50 mm F/1.4
Code: 105758

According to the range of focal lengths, lenses are divided into fixed and zoom lenses. Fix - any lens with a fixed focal length, a slang word, an abbreviation used to contrast with zoom lenses.

Vario lens - a lens with a variable focal length (zoom, "zoom").

Each type of lens has both pros and cons, which, however, are quite subjective. Primes, for example, are much lighter and more compact, but zooms are much more versatile in terms of focal lengths. In some situations (a wedding reportage, for example), the zoom will allow you to get the necessary composition with minimal effort to change lenses and constant movement. If we compare fixes and zooms that are close in aperture ratio and focal lengths, then you can sometimes get a twofold superiority of the zoom in weight, which you will certainly feel, and the cost will be higher.
In addition to the focal length, there is another important detail that amateur photographers should know about - the crop factor of the matrix.
The thing is that there are so-called "normal" lenses - the perception of perspective in photographs taken with the help of such a lens is as close as possible to the perception of perspective by the human eye. The parameters of such lenses were calculated in the days of film cameras, which used 35 mm film. The focal length of this lens turned out to be 50 mm.
However, the sensors of most modern SLR cameras are smaller than a frame on 35 mm film (crop sensor). Because of this, the part of the image at the edges captured by the lens simply does not fall on the matrix, that is, the viewing angle decreases. Therefore, for convenience, the term "equivalent focal length" is used for crop-matrix cameras - such a focal length at which the angle of view will be the same as on film at the actual focal length.
Simply put, modern crop-matrix SLR cameras are designed in such a way that the photos are a little closer compared to the frames taken on a film camera or full-frame (full frame) matrices. It should be noted that lenses on all formats give the same image, the resizing of which depends only on the size of the matrix. Below is a picture for understanding. The red frame shows the borders of a regular 36×24 mm frame, the blue one shows the borders of a 22.5×15 mm digital camera frame.

Usually, in the descriptions of cameras, the so-called "crop factor" is indicated - a coefficient showing how many times the linear dimensions of the matrix are smaller than the dimensions of the film frame. As a rule, for modern SLR cameras this value is in the range of 1.3-2.0. Among them, the most common crop factors are 1.5 and 1.6 (APS-C standard) and 2 (4:3 standard (4/3 and Micro 4/3)). To calculate the equivalent focal length, you need to multiply the focal length indicated on the lens by the crop factor of the camera. For example, you need to compare two lenses designed for different cameras:
1. The SMC Pentax-DA lens is marked "18-55 mm". The crop factor of the camera on which this lens is mounted is 1.53. Multiplying the focal lengths by the crop factor, we get the equivalent focal lengths (EFF): 28-84 mm.
2. The lens of the Olympus C-900Z camera is marked "5.4-16.2 mm". The crop factor of this device is 6.56. Multiplying, we get the EGF of the lens: 35-106 mm.
Now, we can compare them. The first has a wider angle of view at a wide angle, the second - a longer telephoto.

Classification of lenses according to the angle of the field of view (focal length).

The classification of photographic lenses by the angle of the field of view or by the focal length related to the frame size is widely used. This characteristic largely determines the scope of the lens.

Schematic designation of the focal length and their angle of view: 1. Super wide-angle lens. 2. Wide angle lens. 3. Normal lens. 4. Telephoto lens. 5. Super telephoto lens

A normal lens is a lens whose focal length is approximately equal to the diagonal of the frame. For 35 mm film, a lens with a focal length of 50 mm is considered normal, although the diagonal of such a frame is 43 mm. The field of view of a normal lens is between 40° and 51° inclusive (often around 45°). The field of view of such a lens is approximately equal to the field of view of the human eye. Such lenses do not introduce distortion into the perspective of the frame.

Wide-angle (short-focus) lens - a lens with a field of view angle of 52° to 82° inclusive, the focal length of which is less than the wide side of the frame (20-28 mm). Objects in the background when shooting with this lens are smaller than what we see. Often used for shooting in confined spaces, such as interiors, but can be distorted. Also used for shooting landscapes and architecture.

TAMRON SP AF10-24mm F/3.5-4.5 Di II LD Canon Lens
Code: 153710

An ultra-wide-angle lens is a lens with a field of view of 83° or more and a focal length shorter than the small side of the frame (less than 20 mm). Ultra wide-angle lenses have an exaggerated perspective and are often used to add extra dimension to an image. Fish-eye lenses (fisheye) have an angle of view of about 180 ° and give even more distortion.

Lens TOKINA 11-16 f/2.8 DX AF for Canon
Code: 163907

Lens TOKINA 10-17mm f/3.5-4.5 AF DX Fish-Eye for Nikon
Code: 163906

Portrait lens - if this term is applied to the range of focal lengths, then it usually means the range from the diagonal of the frame to three times its value. For 35mm film, a portrait lens is considered to have a focal length of 50-130mm and a field of view of 18-45°. The concept of a portrait lens is conditional and refers, in addition to the focal length, to the aperture ratio and the nature of the optical pattern as a whole. Lenses are quite versatile. In photographs taken with this lens, objects in the background are smaller than what we see. Another issue is that when shooting portraits, they usually try to blur the background.

Canon EF 28-135 f/3.5-5.6 IS USM Lens
Code: 112705

A telephoto lens (often referred to as a telephoto lens) is a lens whose focal length is much longer than the diagonal of the frame (150 mm). It has an angle of view from 10° to 39° inclusive, and is designed for shooting distant objects.

Olympus M.ZUIKO DIGITAL ED 75-300mm 1:4.8-6.7 lens
Code: 159180

Lens aperture.

Aperture is the second most important lens parameter. Most often, under the aperture ratio of the lens, the value of the denominator of the relative aperture (aperture number) is misunderstood. The aperture value, the value of which is printed on the lens, only numerically characterizes the aperture ratio.
Generally speaking, lens aperture is a value that characterizes the degree of attenuation of light by the lens. Aperture, more precisely, geometric aperture, is proportional to the area of ​​​​the effective aperture of the lens, divided by the square of the focal length (the square of the so-called relative aperture of the optical system). That is, it depends on the geometric parameters - the diameter of the hole and the length. The effective opening of the lens is the opening that determines the diameter of the beam of incoming light falling on the film or matrix. If we consider the lens as a simple tube, then with the same diameter, more light will pass through a shorter one. Accordingly, in order to improve the luminosity of a longer tube, we will have to increase its diameter. When passing through the lens, light is absorbed by the glass, scattered by the lens surface, experiencing various reflections inside the lens, etc. The luminosity that takes into account all these losses is called the effective luminosity.
As mentioned above, a lens is a system of lenses in a frame through which light passes and is recorded by a photosensitive element. This frame contains an adjustable "limiter" of the light output, called a diaphragm.

The wider the aperture is open, the more light will hit the matrix, the brighter the picture will be. The aperture size versus f-number is illustrated below.

Moving the aperture by one division changes the relative aperture by ≈1.41 times, while the illumination changes by a factor of two. The aperture scale is standard and looks like this: 1:0.7; 1:1; 1:1.4; 1:2; 1:2.8; 1:4; 1:5.6; 1:8; 1:11; 1:16; 1:22; 1:32; 1:45; 1:64. However, the first aperture numbers on the lenses may not coincide with the standard ones (1:2.5; 1:1.7). Typically, f-numbers are printed on lenses and indicate the maximum aperture at a given focal length.

Using the aperture, you can not only adjust the amount of light, but also set the required depth of field (DOF). In other words, adjusting the aperture affects the blurring of the background. The more the aperture is opened, the shallower the depth of field will be (more blurred background). This technique is usually used for portraits, that is, where a strong emphasis on the foreground object is needed. An open diaphragm forms a circle, a partially closed diaphragm forms a polygon. “Bokeh” depends on the type of this polygon - the artistic blurring of point light sources, objects that are not in focus. The more edges (aperture blades), the more beautiful the bokeh.

Lenses may have one or two (for zooms) aperture values. That is, there is a constant and variable lens aperture.

Nikon Nikkor AF-S 50 mm f/1.4 G Lens
Code: 300145

Lens Sony SAL-1118 DT 11-18 mm F4.5-5.6
Code: 102042

Constant luminosity is characteristic of fixes. For zooms, a change in focal length entails a change in aperture ratio (as we remember, it is inversely proportional to the square of the focal length). However, zooms can also have a constant aperture. This is quite convenient, for example, when shooting with flash, since there is no need to take into account the change in aperture. Such lenses are always somewhat more expensive due to the complexity of the design.

Typical values ​​of the denominator of the maximum relative aperture of lenses of different classes:
Small-scale unique lens for the NASA space program Carl Zeiss Planar 50mm f/0.7: 0.7.
Leica Noctilux for rangefinder camera: 0.95.
Jupiter-3 for a rangefinder camera (Zonnar optical design): 1.5.
Prime lenses for SLR: 1.2 - 4.
Digital autofocus compact camera: 1.4 - 5.6.
Mid-range zoom lens for SLR: 2.8 - 4.
Inexpensive zoom lens for a SLR camera: 3.5 - 5.6.
Autofocus compact camera: 5.6.
Film compact camera: 8 - 11.

To understand all of the above: a faster aperture lens is one with a smaller aperture value. For amateur photography, the average value of f / 4 is usually enough. Therefore, for beginners, inexpensive f/3.5 - f/5.6 zooms can be recommended, which will be enough for most everyday tasks.

Stabilizers and ultrasonic motors.

When shooting in low light conditions or at slow shutter speeds, the shots often come out blurry. Due to hand shaking or other reasons, the frame may be irreparably damaged. This is where technology comes in to help stabilize the image.
The camera has built-in special sensors that work on the principle of gyroscopes or accelerometers. These sensors constantly determine the angles of rotation and speed of movement of the camera in space and issue commands to electric actuators that deflect the stabilizing element of the lens or matrix. With electronic (digital) image stabilization, the angles and speeds of movement of the camera are recalculated by the processor, which eliminates the shift.
There are three types of stabilizers: optical, with a movable matrix and digital.

Optical image stabilizer.
In 1994, Canon introduced a technology called OIS (Eng. Optical Image Stabilizer - optical image stabilizer). The stabilizing element of the lens, which is movable along the vertical and horizontal axes, is deflected by the electric drive of the stabilization system at the command from the sensors so that the image projection on the film (or matrix) fully compensates for camera vibrations during exposure. As a result, at small amplitudes of camera vibrations, the projection always remains stationary relative to the matrix, which provides the picture with the necessary clarity. However, the presence of an additional optical element slightly reduces the aperture ratio of the lens.
Optical stabilization technology has been picked up by other manufacturers and has proven itself in a number of telephoto lenses and cameras (Canon, Nikon, Panasonic). Different manufacturers call their implementation of optical stabilization differently:

Canon - Image Stabilization (IS)
Nikon - Vibration Reduction (VR)
Panasonic - MEGA O.I.S.(Optical Image Stabilizer)
Sony Optical Steady Shot
Tamron - Vibration Compensation (VC)
Sigma - Optical Stabilization (OS)

For film cameras, optical stabilization is the only technology to combat "shake", since the film itself cannot be moved like a digital camera matrix.

Image stabilizer with a moving matrix.
Especially for digital cameras, Konica Minolta has developed stabilization technology (English Anti-Shake - anti-shake), first used in 2003 in the Dimage A1 camera. In this system, the movement of the camera is compensated not by the optical element inside the lens, but by its matrix, fixed on a movable platform.
Due to this, lenses become cheaper, simpler and more reliable, image stabilization works with any optics. This is important for SLR cameras with interchangeable lenses. Matrix-shift stabilization, unlike optical stabilization, does not introduce distortions into the image (perhaps, except for those caused by the uneven sharpness of the lens) and does not affect the aperture ratio of the lens. At the same time, matrix-shift stabilization is considered to be less effective than optical stabilization.
With an increase in the focal length of the lens, the effectiveness of Anti-Shake decreases: at long focuses, the matrix has to move too fast with too large an amplitude, and it simply ceases to keep up with the "elusive" projection.
In addition, for high accuracy, the system must know the exact value of the focal length of the lens, which limits the use of old zoom lenses, and the focusing distance at close range, which limits its work in macro photography.
Motion Matrix Stabilization Systems:

Konica Minolta - Anti-Shake (AS);
Sony - Super Steady Shot (SSS) - is a borrowing and development of Minolta's Anti-Shake;
Pentax - Shake Reduction (SR) - developed by Pentax, found application in Pentax K100D, K10D and subsequent SLR cameras;
Olympus - Image Stabilizer (IS) - used in some models of SLR cameras and Olympus "ultrasounds".

Electronic (digital) image stabilizer.
There is also EIS (Eng. Electronic (Digital) Image Stabilizer - electronic (digital) image stabilization). With this type of stabilization, approximately 40% of the pixels on the matrix are assigned to image stabilization and do not participate in image formation. When the video camera shakes, the picture "floats" on the matrix, and the processor captures these fluctuations and makes a correction using spare pixels to compensate for the picture shake. This stabilization system is widely used in digital video cameras, where matrices are small (0.8 Mp, 1.3 Mp, etc.). It has a lower quality than other types of stabilization, but is fundamentally cheaper, since it does not contain additional mechanical elements.

Modes of operation of the image stabilization system.
There are three typical modes of operation of the image stabilization system: single or personnel (English Shoot only - only when shooting), continuous (English Continuous - continuously) and panning mode (English Panning - panning).
In the single mode, the stabilization system is activated only for the duration of the exposure, which is theoretically the most effective, since it requires the least corrective movements.
In continuous mode, the stabilization system works constantly, which makes it easier to focus in difficult conditions. However, the effectiveness of the stabilization system in this case may turn out to be somewhat lower, since at the time of exposure the corrective element may already be displaced, which reduces its adjustment range. In addition, the system consumes more power in continuous mode, which drains the battery faster.
In panning mode, the stabilization system compensates only for vertical oscillations.
It's fair to assume that the presence of stabilization in the lens affects the cost. Therefore, with a limited budget, it is worth deciding how critical this parameter is for you. Stabilization makes more sense when shooting distant subjects, poor lighting, or slow shutter speeds. Accordingly, if you are looking for a wide-angle or portrait lens for shooting mostly static subjects, you can save on stabilization.
In some cases, fast focusing on the subject is important to get a great shot. To do this, manufacturers equip some of their lenses with more expensive ultrasonic (piezoelectric) motors.

Ultrasonic auto focus lens motor.

Here is a list of designations from various manufacturers:
Canon - USM, UltraSonic Motor;
Minolta, Sony - SSM, SuperSonic Motor;
Nikon - SWM, Silent Wave Motor;
Olympus - SWD, Supersonic Wave Drive;
Panasonic - XSM, Extra Silent Motor;
Pentax - SDM, Supersonic Drive Motor;
Sigma - HSM, Hyper Sonic Motor;
Tamron - USD, Ultrasonic Silent Drive, PZD, Piezo Drive.

Purpose of lenses.

The purpose of the lens is essential. Before you start shooting, there is always the question of what we are going to shoot. By purpose, lenses are divided as follows:
portrait lens- Used for taking portraits. Should give a soft image without geometric distortion. As portrait lenses, telephoto lenses or lenses with a fixed focal length in the range of 80-200 mm (for 35 mm film) are often used. The classic ones are 85 mm and 130 mm. A specialized portrait lens is designed in such a way that it shows minimal aberrations when focusing from several meters, that is, when shooting a portrait, to the detriment of image quality “at infinity”. A large aperture (better than 2.8) is practically mandatory for a portrait lens, and the nature of the bokeh is very important;
macro lens- a lens specially corrected for shooting from finite short distances. As a rule, it is used for macro photography of small objects close-up, up to a scale of 1: 1. Allows you to shoot with increased contrast and sharpness. They have a smaller aperture ratio than other types of lenses of similar focal length. Typical focal length is 50 to 100 mm. In addition, it usually has a special frame;
Long lens- usually used for shooting distant objects. A telephoto lens in which the distance from the front optical surface to the rear focal plane is less than the focal length is called a telephoto lens;
reproduction lens- used when reshooting drawings, technical documentation, etc. Must have minimal geometric distortion, minimal vignetting and minimal curvature of the image field;
shift lens(lens with a shift, from the English shift) - is used for architectural and other technical shooting and helps prevent perspective distortion.
tilt lens(lens with a tilt, from the English tilt) - is used to obtain a sharp image of extended objects that are not perpendicular to the optical axis of the lens during macro photography, as well as to obtain artistic effects.
Tilt-shift lens- a class of lenses that combines the shift and tilt of the optical axis. Allows you to use the capabilities of gimbal cameras in small format photography. The largest manufacturers of photographic equipment have at least one such lens in their line of optics, for example, the Canon TS-E 17 F4L.
stenop(pinhole) (a pinhole camera lens, a small hole, from the English pinhole) - is used for shooting landscapes or other objects with very slow shutter speeds and obtaining an equally sharp image from macro distances to infinity in one frame;
Soft lens(soft lens, from English soft) - a lens with undercorrected aberrations, usually spherical, or with distorting structural elements. Serves to obtain the effect of blur, haze, etc. while maintaining sharpness. Used in portrait photography. A slightly similar effect is given by the so-called "soft focus filters";
Superzoom(travel zoom) (eng. travel zoom) is a universal zoom lens of relatively low weight and maximum range of focal lengths. It is used with reduced requirements for image quality and increased requirements for efficiency of use and weight.
Ultrazoom- superzoom, which is characterized by increased magnification of the range of focal lengths, usually starting from five.
Hyperzoom- super zoom, the focal length range of which is usually more than 15. Common in professional camcorders and compact cameras, for example, Fujinon A18x7.6BERM, Angenieux 60x9.5, Nikon Coolpix P500 (36 magnification), Sony Cyber-shot DSC-HX100V (30 magnification) ), Canon PowerShot SX30 IS (35x), Nikon Coolpix P90 (24x). The image quality of the lens required in video cameras, especially standard definition, allows you to build lenses with high magnification. In addition, with a small diagonal of the matrices of video cameras and compact cameras, the dimensions of a zoom lens with a large range of focal lengths are incomparably smaller than they would be with the same parameters for the APS-C format. Studio camcorders can be equipped with zoom lenses with a magnification of 50 or even 100.

Lens mount methods.

According to the method of fastening with the body of the device (camera, movie camera, film projector, overhead projector, etc.), lenses are divided into threaded and bayonet - the first are mounted on the camera flange by screwing along the thread, the second are fixed in it by turning. In the simplest designs, lenses are held only by friction or are clamped by a clamp-like holder. Bayonet lens - (from French baïonnette - bayonet) - a type of connection designed to mount the lens to photographic, filming devices, video cameras and digital cameras. The main advantage over screw mounts is the exact orientation of the lens relative to the camera, mainly in relation to its mechanical and electrical connections. This is especially important for the mechanical transmission of the set aperture value to the exposure meter and the alignment of the electrical contacts of modern lenses with microprocessors. In addition, some lens frames require precise orientation in order to properly mount accessories such as macro devices, follow focuses, and compendiums. A more technologically advanced and cheaper threaded mount was replaced by a bayonet mount in the 1950s, since the thread does not provide sufficient accuracy in relative orientation. Another advantage of the mount is the faster lens replacement.

Today there are many different types of mounts, so when buying a lens (especially in the secondary market), you need to make sure that this lens is compatible with your camera. One of the two types of mounts that have remained unchanged since the advent of autofocus and digital photography is the Nikon F (F mount). This is a standard for bayonet attachment of lenses to small-format single-lens reflex cameras, first used by Nikon Corporation in the Nikon F camera in 1959, and with some changes used to this day, including in digital cameras. Another type of K mount, which has survived to this day, was developed by Asahi Pentax. The remaining mounts are considered obsolete and have been replaced by fundamentally new ones, incompatible with previously released photographic equipment.
However, sometimes there is a desire to use in your work some lens with an outdated or inappropriate mount (from the old Zenith, for example) with your SLR camera. For lovers of vintage optics and experiments, there are various adapters and adapters that allow you to install lenses with a different mount.

Adapter M42 - Nikon F with a lens and a chip.

Lens choice.

For general shooting at home, portraits of friends, street scenes and much more, the standard "whale" lens that comes with the camera is more than enough for a beginner. They have focal lengths of 18 - 55 mm or 18 - 105 mm, suitable for most ideas. An even more versatile lens can be purchased, covering the entire range from wide-angle to telephoto (focal length 18-200mm), such as the TAMRON AF 18-200/3.5-6.3 XRLD DII, which remains the lightest and most compact zoom lens in the world.

TAMRON AF 18-200 / 3.5-6.3 XRLD DII Nikon lens
Code: 136362

If you gravitate toward photography and want to plunge into the world of photography as much as possible without any special expenses, then it makes sense to buy a fixed lens for a standard lens. For example, everyone's favorite "fifty dollars" is a lens with a focal length of 50 mm or even 35 mm. With such a lens, you can get decent bokeh, appreciate its aperture ratio and feel like a real photographer, moving around in search of composition. Plus, it's light and compact, making it a pleasure to work with.

Nikkor AF-S DX 35mm f/1.8 G Lens
Code: 126699

For shooting distant objects, a lens with a focal length of 70-300 mm is suitable, for example, Tamron SP AF 70-300mm F / 4-5.6 Di USD:

Tamron SP AF 70-300mm F/4-5.6 Di USD lens for Sony
Code: 160453

For those who want to take macro photos, there are inexpensive solutions in the form of lenses like:

Canon EF 50 mm F2.5 compact-macro lens
Code: 103480

There is an even more budget option - various nozzles and macro rings.
Macro attachments are special lenses that are screwed onto the lens. They give quite a lot of distortion.
Reversing rings are devices for fixing the lens on the carcass backwards. The magnification is excellent, but there is no way to control aperture.
Macro rings are the most suitable option for trying your hand at macro photography. They allow you to achieve a good increase, however, like any additional glass in the system, they give some distortion and lead to a drop in aperture ratio.

Samyang 500mm f/6.3 aka Bower, aka Rokinon, aka Polaroid. Five hundred millimeters, cheap price and small dimensions are the characteristics that attract many fans of the genre, and they are also its only advantages. Unfortunately, it has no other advantages.

What is a reflex lens?
This is a catadioptric optical system in various modifications, of which the Schmidt-Cassegrain and Maksutov modifications are the most common. In such schemes, the light hits the camera's matrix by reflecting several times from the mirrors inside the lens. There are two mirrors inside: main and secondary, but in addition to mirrors, the lens has corrective lenses. The quality of all these elements depends on the image. But in addition to the quality of the elements, the image also depends on the central screening (CE). The sharpness of the image also depends on the CE. The more shielding, the worse the sharpness. The central shielding can be determined by the formula:
Dtsk * 100 / Dgl.z, where:
Dgl.z is the diameter of the main mirror (Samyang = 90mm)
Dtsk is the diameter of the central fastener. (Samyang=40mm)
As a result, we get the percentage of central shielding. If it turns out more than 30 percent, then you will not see sharp images. The Samyang lens has a CE of 44.5 percent, from which we can immediately conclude that when photographing wildlife or sports, you will not see the contrast of small details (feathers, hair, etc.), everything will be blurred.
The lens itself is very well made. The metal body, rubberized focus ring and coated lenses, together with a high-quality assembly, look quite solid.

Lens parameters according to the manufacturer's website http://samyang.ru
Focal length: 500mm
Construction: 7 elements / 6 groups
Field of view angle: 5
Focus: manual
Minimum focusing distance: 2m
Minimum aperture: none
Bayonet: T-mount
Number of aperture blades: none
Relative aperture: f/6.3
Dimensions: 105.0 x 98.0 mm (without adapter)
Hood: not included
Weight: 645

Which of these parameters will we be interested in.
The first is the lack of a diaphragm, that is, it will not work to cover it, this is a feature of all mirror-lens lenses.
The second is the bayonet. This mount is not found in any modern camera, so special adapters from the T-mount mount to the mount of various cameras were invented. Such adapters are called T-rings and are sold at any photo store at a price of 300 to 600 rubles.
The third is the relative aperture, which is 6.3. But if we compare the mirror-lens Samyang and a refractor, for example Sigma 150-500, then the picture will be darker in the Samyang lens, as can be seen from the photos. Shutter speed, ISO and other settings are the same:
photo from Samyang 500mm f/6.3 (100% crop)

photo taken with Sigma 150-500mm f/6.3 (100% crop)

You can immediately pay attention to the sharpness. In both cases, manual focusing was used. As for manual focus, this is another not-so-nice option for a Samyang lens. With manual focus and a 5-degree field of view, it's quite difficult and annoying to catch any moving object and focus. In this way, you can only photograph calm animals and buildings, and birds, people, cars or flying objects are unlikely to succeed. Focusing is done by moving the tube with a rubberized ring:

I offer a couple of examples with attempts to photograph:

For comparison, here is what happens with the Sigma 150-500 autofocus:

From experience, I can say that Samyang 500mm is not of high quality photos. Rather, such a lens will let you know whether you need this genre or not. You can try it in astrophotography, but don't expect sharp shots.
You can buy a magnifying extender for the lens, which doubles the focal length, however, the image becomes twice as dark, and the quality also suffers.

The extender is here just for fun, in addition to worsening sharpness, chromatism is also added. the next frame is 100% center using the extender. Words are superfluous, the photo shows everything:

You can also remove one of the objective lenses, which is responsible for field correction. As a result, the focal length will increase, and the rest of the indicators will remain unchanged. But this is the case when used on an APS-C format matrix, vignetting will most likely appear on the FF

And here's what happens when you compare the two options. Left without corrector, right with corrector:

It's up to you to buy it or not, but you won't get the pleasure of shooting wildlife, moving objects or sports.

All pictures were taken with Sony SLT-a33.

Sincerely, Lifintsov Ivan.

After some time after purchasing the camera, the standard lens begins to bother and you want something new. It always seems that other lenses would make it possible to take much better photos, and then the search for a candidate for the title of a new, beloved lens begins. Going to any site that sells lenses, you can see that their prices start from a few thousand rubles and go up to several thousand dollars. Of course, you start looking for the reason for such a discrepancy in prices.

In photography, there is an unwritten law: "the more expensive - the better."

However, there are exceptions here too. The fact is that the most expensive lenses are designed to solve some specific, specific tasks, for example, shooting sports.

Naturally, there is not the slightest sense in paying a lot of money for such a lens, especially since it will be used for normal shooting, and the weight of such a thing is not small. In short, do not chase the most expensive device. Moreover, there will be practically no difference from using a specialized lens and a regular fifty dollars. It is worth noting that the prices for 50mm lenses are quite low and start at 4 thousand rubles.

So after all, for what characteristics do we pay money and what properties should a modern lens have? Of course, an expensive lens, first of all, must have excellent optical qualities.

Lens Resolution

Aperture

Chromatic aberration

Vignetting

distortion

1. 1. when shooting, move a little further from the subject and use the zoom. 2. remove distortion programmatically 3. use more expensive lenses 4. use a lens with a wider angle

The first way is quite clear. A smaller angle of view gives less distortion. Processing can be difficult. If your picture shows only distant objects, then you can safely use Photoshop plugins. You can use PTLens or a DxO Optics RAW converter. However, if your image contains both near and far objects, it may be difficult to correct. The fact is that objects at different distances from the lens are distorted in different ways. Purchasing a better and more expensive lens will not completely solve the problem. Of course, distortion will decrease, but not significantly. The only effective way to get rid of distortion is to use an ultra wide angle lens like the Sigma AF 10-20mm f/4-5.6. At 10mm, distortion will still be noticeable, but at 14mm it will be almost impossible to see.

However, there are ultra wide-angle lenses that are intentionally made in such a way as not to eliminate distortion. This optic is called Fish eye. Pictures taken with this lens are very unusual. This can end the description of the technical characteristics of the lenses, but there are two more optical characteristics. They cannot be measured, but they are worth describing.

Drawing and bokeh

This concludes the discussion of the technical characteristics of lenses and draws a small conclusion. It is impossible to buy optics with excellent characteristics and a simple design for little money. The fact is that with an increase in the resolution of the lens, the pattern and bokeh are lost, with an increase in the aperture ratio, chromatic aberrations appear and the contrast decreases.

Constructive

Firm

There is a legend among the people that Canon deliberately increases the price of its red ring lenses by $200-300. And that's just for the red ring itself. In fact, this is not entirely true, or rather, the price does not increase for the ring. The ring itself is a sign of quality. In this case, we pay for the brand and for the quality of the product that it offers us. Such a lens is designed not only to raise your status among photographers. The fact is that manufacturers of high-quality optics are confident in their products and, as a rule, they give a guarantee for at least two years, unlike third-party manufacturers who guarantee the lens to work for a maximum of a year. Therefore, when buying lenses from Nikon or Canon, we get a device that can be operated in quite aggressive conditions while guaranteeing the safety of operation. Here's what Canon's warranty cards look like:

It turns out that when buying an expensive lens, we pay for its optical characteristics, build quality, materials, design and brand. It is the brand that is a guarantee of the quality of the goods and the availability of warranty workshops. Yes, the name of the manufacturer and the service really have to overpay a lot of money. Of course, if you still bought a “made in Japan” lens, then you should prepare for additional expenses for various covers, protective devices and other accessories. Of course, you can find analogues made in China for a third of the cost of the originals, but let's look at this in more detail. Take, for example, Canon's signature lens hood. It protects the lens not only from sun glare, but also protects the device from dust settling in the area of ​​​​optical elements and softens head-on collisions with objects. Will the Chinese lens hood provide this level of protection? Possibly, but there is no certainty. Is it worth risking an expensive lens because of the price difference for accessories of just a couple of hundred rubles? Most likely not worth it. What else can be added? A good DSLR will last two or three years before the shutter breaks with intensive work. Then it can be repaired and it will work a little more. Then a new model will come out and in three years it will also break, and a good lens will outlive both the first camera and the second. In addition, a quality lens will never get old. In years to come, he will continue to perform his functions as before.

Based on materials from the site:

Digital technology, designed to make life easier for the photographer, has actually multiplied the number of questions that arise in his head. For a beginner, the task of orienting in the abundance of information about cameras and lenses in general will seem like a Chinese letter. Especially when experts immoderately pour technical terms. Everything seems like a dark forest, but this is only at first glance, you just need to understand what creative tasks you are going to solve.

The lens consists of a tube (plastic or metal) with glasses on both sides (the number of lenses in it can reach 20), aperture blades and an autofocus motor.

There are not so many main parameters: focal length (the gap between the optical center and the sensor), aperture ratio (the degree to which the lens transmits the real brightness of the object) and stabilizer (focusing when shooting without a tripod and in poor lighting).

What do you like more - abandoned industrial buildings, blooming gardens, starry sky, people with a textured appearance, the busy life of weevils? This depends on the choice of lens.

A whale is not an animal...

The option lying on the surface is the so-called "whale" (from the English kit - kit) lens. In the line of manufacturers, they are the cheapest. Perhaps this is the most affordable entry into the world of professional photography, because "whales" usually come with a camera.

It is unpretentious and quite suitable for you in order to deal with the basic parameters and your own creative tasks.

The most common focal length of "whales" is 18-55 mm. Their aperture is not high, this will create problems when shooting in a dark room. But the minimum that the whales give is enough in the early stages.

Photo gurus at the word "whale" contemptuously snort, it's just that for them this is a passed stage. Once you decide that shooting friendly get-togethers in the bosom of nature is not the limit of your dreams, this is an occasion to consider buying a special lens. Although, no one has canceled the fact that in magical hands the “whale” works wonders. It is not uncommon for photographs taken with such a lens to win prestigious international competitions.

The raking eye of the wide-angle

50mm is the standard focal length.Anything less is wide-angle, anything more is telephoto.

If it is vital for you to fit the Red Square, the Eiffel Tower or capture the panorama of the sunset sky into the lens, a wide-angle lens will suit you. He is one of the three most common among both professionals and amateurs.

There are two types of lenses: fixed focal length (Fix) and zoom (Zoom). The former do not bring the object closer, so you will need to approach it yourself, while the latter make it possible to approach while standing still. “Fixes” are superior to “zooms” in aperture ratio. Such lenses make distant objects close and vice versa. If you skillfully use these opportunities, you can achieve high results.

Big is seen from a distance and not only

When shooting distant subjects (want, for example, to shoot a wombat in its natural habitat and not scare it away), you will need a telescopic lens that belongs to the telephoto lenses.

But it would be a mistake to think that the capabilities of the telephoto lens are exhausted at this point. With it, you can change the perspective and look at familiar things with a different look, because when using it, the difference between near and far objects is smoothed out. And their ability to visually compress the distance between objects is useful if you need to create the effect of density and emphasize the multiplicity of some objects (for example, you are filming some grandiose mass bike ride or a flower meadow).

• It should be remembered that telephoto lenses have a small angle of view, so when using it, you should be more scrupulous in choosing what will be in the frame. You can film a guitarist performing a guitar solo or a swift in flight.

Universe in a drop of dew

Let us have at least three times the era of nanotechnology, a person still feels best in nature. Far from neon and plastic, he turns into the same person he was tens of thousands of years ago - a pioneer. One has only to take a closer look around, or rather, look under one's feet. Here are the inhabitants of an anthill, en masse dragging a bronze beetle to the slaughter, here is a drop of dew on a water lily, here is a dragonfly sitting on a lily. It's time to capture all this beauty. It is best to use a macro lens.

A macro lens is capable of shooting life-size (i.e. 1:1) and even larger (2:1 and above).

Some manufacturers indicate a magnification factor instead of a scale (1x, 2x b, etc.). If it is not possible to purchase a special lens, for shooting daisies and swallowtails, the already known "whale" lens will fit, which allows you to achieve a scale of 1: 3. To date, most of the day "soap dishes" are also equipped with "macro mode". True, the objects shot by them may have an unnatural perspective, since they have to shoot "point blank". If you really want to reach the heights (or depths) of understanding the world of plants and insects, you will need a lens with a focal length of at least 100mm.

Choose but check

Each company has its own line of lenses, sharpened exclusively for their cameras. Giant companies are strict with this. You can't put a Nikon lens on a Canon camera and vice versa. Some manufacturers, like Tamron and Sigma, make lenses that interface with major label cameras. And the prices for components are twice cheaper. According to the pros, the difference in price affects the quality. By and large, this is true, but we hasten to console you: there are adapters for "non-native lenses".

Here are a few more parameters that should not be ignored:

• Vignetting. If you look closely at some of the photos taken with a wide-angle lens, you can see darkening around the edges.

This is due to the fact that more light enters the center. In some cases, vignetting is used deliberately. When the master is aware of himself, his works acquire individuality and originality. Otherwise, involuntary vignetting is the stigma of an amateur. Ultimately (we are talking about the choice of lens now, right?) - the less such an effect is expressed in the lens, the better. Experienced photographers advise choosing attached lenses with the lowest rim. Photoshop will allow you to eliminate blackouts or artificially create them.

• aberrations. Even professional lenses are prone to this ailment. It manifests itself in the fact that a rainbow blooms along the edges of particularly contrasting areas or a single color stands out. For example, blue or green. You can avoid this effect with the help of Photoshop or by buying yourself a more expensive model, which, however, is not always a panacea.

• Focus speed. Cheap lenses focus slower.

• Dust / moisture resistance. Kit lenses are more susceptible to moisture and sand penetration. And Canon L-series lenses can survive even tropical downpours, even the most in the Sahara desert. But the price is right too.

• Stabilizer. It is necessary in order to minimize the consequences of natural fluctuations inherent in a person and not to blur the photo. With it, you can shoot at shutter speeds that exceed the average assumptions.

• Bayonet. With this device, the lens is attached to the camera. Each company has a unique mount. That is why a lens for Nikon is not suitable for a Canon camera.

Whether you're buying a wide-angle or fisheye lens, it's important to check it out. Check the mechanics - there should be no squeaks and jams. Retractable lenses are generally prone to clogging - keep that in mind.

It is important that the lens is clearly focused on the objects you are going to shoot. When buying from your hands, be sure to check the focus.

Be that as it may, start with the optics that are available to you. You can borrow an expensive lens from a friend or rent it and see if you really need it or if it will be money thrown away.