What does usm mean? Markings on the lens. Canon lens markings

As you may have guessed, Canon has a whole carload of lenses. There is everything for every type of shooting. Not long ago, STM lenses became available for sale.

They come in the “Whale” configuration of new models of Canon SLR and amateur cameras.

What are STM lenses? STM is a focusing mechanism technology based on the use of a stepper motor (motor).

This lens is easy to recognize; it has a special STM marking. On this moment Canon has only 4 STM lenses, more on them later.

So, what benefits does STM give us? I’ll say right away that this will not affect the image quality (well, or not at all significantly). Because the glass remained the same, only the motor that rotates the focusing lens of the lens was changed, now the front lens does not rotate and you can use any filters without any obstacles. The main advantage of the STM motor is fast and silent focusing.

At first glance, it is not inferior to USM...

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lenses over short distances, and with an extremely low noise level.
Lenses with STM technology in combination with cameras that provide
phase focusing using...

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What is a USM lens? what is an STM lens? How is a USM lens different from an STM? Canon which one is better...

Ultrasonic driven lenses are marked with the abbreviation USM in their name.
Ultrasonic drive autofocus system appeared in the lens
EF 300 mm f/2.8L USM in 1987. Canon became the first manufacturer
who have applied similar technology in their products. Lenses,
equipped with a USM motor, provide faster focusing,
make less noise and consume less less energy compared with
conventional motors used in lenses.

In 2012, together with a Canon EOS 650D camera equipped with a matrix,
in which part of the pixels is intended for focusing using the phase difference method,
The first two lenses with a stepper motor (STM stepper motor) were presented.
This technology allows for multiple rapid movements of the focus group
lenses over short distances, and with an extremely low level...

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For some reason, many readers perceived Canon's release of stepping motor (STM) lenses as just an update on the road to smoother video shooting. However, STM lenses also provide higher-quality images in photos, plus they differ from their predecessors in some ways technical parameters, which expand the boundaries of their application and make them more convenient. In this article I want to talk in more detail about the advantages of the new version of the lens using the Canon EF-S 18-135 IS and STM as an example.

In my opinion, the Canon EF-S 18-135 IS is one of the best for everyday shooting. It provides good image quality for an undemanding user, combines a wide range of focal lengths, reasonable size and weight, and a low price. This is perhaps the best choice for those who are buying for the first time. SLR camera, and for those who want to get a universal all-in-one lens for traveling or just shooting various scenes. A a new version Canon EF-S 18-135 IS STM...

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Canon lens markings

The first Canon SLR cameras to replace rangefinder cameras appeared in 1959 and had a Canon R mount. In 1964, it was replaced by a Canon FL mount, which in turn gave way to a Canon FD mount in 1971. However, with the advent of the autofocus lens era in 1987, Canon once again developed a completely new standard– Canon EF, which is still relevant today. Unlike Nikon, which has remained faithful to the Nikon F mount since 1959, thereby ensuring relative compatibility between modern cameras and vintage lenses, Canon began its history in 1987 with clean slate, and therefore Canon’s principles of compatibility are very simple:

All Canon EF lenses are fully compatible with all Canon EOS cameras, both full-frame and cropped (APS-C). Canon EF-S lenses are designed for cameras with a crop factor of 1.6 and are not compatible with full frame cameras....

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I’ll dilute a little the theoretical reasoning of the owners of 1.4

I had 40/2.8 at the beginning. People didn’t like it - it doesn’t separate it from the background, you can’t get close to it. Not needed for my purposes.

After that I took 1.4. In terms of sharpness, from about 2.2 it was normal on 5D2. But there was one BUT - the percentage of hits was unsatisfactory. I hit it more or less normally only on a hole of 2.8 or narrower.
Which didn’t suit me too much; I wanted to shoot normally at 2.2.

As soon as it appeared, I bought 50/1.8stm. I took paired shots with 50/1.4.

The result is up to 2.5 identical glasses in sharpness. From 2.8 1.4 starts to be a little sharper.
An important BUT - 1.8 was much more stable in terms of AF performance, the 2.2 hole worked stably.
The comparison shots showed that the 1.4 version produces warmer images and blurs the bokeh a little smoother.

As a result, I sold the 1.4 version without regret and kept the 1.8stm. I don't need any blur if the glass doesn't get at least 90% hits...

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In this article we will help you understand the symbols that mark Canon lenses. Let’s make a reservation right away that we will only consider lenses produced for the modern EF mount (and its derivatives). The reason for this “narrowing of boundaries” is that older lenses stopped being developed in 1987, due to a change in the approach to camera packaging and the advent of the EOS system, they are rare, and most importantly, they are not compatible with modern models cameras from a Japanese manufacturer.

EF (Electro Focus) is a marking found on all modern Canon lenses (or rather, almost all, but more on that below). This is the designation of the bayonet (lens mounting system with the camera).

In 1987, Canon, the first in the world among photo equipment manufacturers, took a risky, but at the same time very far-sighted step, introducing a bayonet mount in which the mechanical connections between the camera and the lens were completely removed. All drive control...

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The website kaddr.com continues a series of articles about the markings and symbols of lenses from global photographic equipment manufacturers. In the last PhotoHack, we looked in detail at the markings of Nikon lenses. Today we’ll talk about their “sacred enemy” and, concurrently, the world leader in the production of photographic equipment...

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When we look at a photograph or watch a video, we immediately pay attention to whether the image is in focus or not.

Since 1987, when Canon became the first to integrate a focus motor into a lens, several motors have been created to focus and track fast-moving subjects. At the same time, focusing remains accurate, smooth and silent.

There are currently three main types of focus motors used in Canon lenses. These are stepper motor (STM), ultrasonic motor (USM) and direct current motor (DC). Let's look at the differences between these motors so you can choose the right lens.

STM

STM lenses allow you to take great photos and better videos. These lenses are equipped with a stepping motor that provides smooth and quiet focusing - two excellent characteristics for video shooting.

Some motors used in lenses make a distinct mechanical sound when focusing, and STM lenses...

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Canon ultrasonic

In the section Selecting, purchasing equipment, answer the question What is a USM lens? what is an STM lens? How does a USM lens differ from an STM? (Canon) which one is better... asked by the author Katyusha - the best answer is Lenses with ultrasonic drive are marked with the abbreviation USM in the name.
Ultrasonic drive autofocus system appeared in the lens
EF 300 mm f/2.8L USM in 1987. Canon became the first manufacturer
who have applied similar technology in their products. Lenses,
equipped with a USM motor, provide faster focusing,
produce less noise and consume less energy compared to
conventional motors used in lenses.
In 2012, together with a Canon EOS 650D camera equipped with a matrix,
in which part of the pixels is intended for focusing using the phase difference method,
The first two lenses with a stepper motor (STM - stepper motor) were presented.
This technology provides multiple...

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Quite recently, one of the leaders in the world of digital equipment, Canon, released two new lenses - EF-S 18-135mm f/3.5-5.6 IS STM and EF 40mm f/2.8 STM. The EF-S 18-135mm f/3.5-5.6 IS STM is a standard zoom lens that can be used for a variety of purposes and occasions. The focal length range - from 18 mm to 135 mm - corresponds to the range from 29 mm to 216 mm on a camera with a 35 mm sensor.

The maximum magnification you can expect using the lens is 0.28x. And if you use the EF12 II extension ring, the increase will be in the range from 0.43 to 0.09, and with the EF25 II extension ring - 0.61 - 0.21.

But the EF-S 18-135mm f/3.5-5.6 IS STM will not work with a teleconverter (or, in Canan’s style, an extender), unlike such EF series models as the EF 70-200mm f/2.8L USM, EF 70-200mm f/2.8L IS USM, EF 70-200mm f/4L, EF 100-400mm f/4.5-5.6L USM, EF 400mm F/4 DO IS USM. So even Canon is perfect...

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If you are wondering what all these letters on your Canon lens mean, then you have come to the right place.

FDs are ancient lenses from Canon that were produced in the 70s-80s. They are not suitable for modern cameras, so such a lens can only be attached to a modern camera with an EF mount using a special adapter. Unlike Nikon, Canon changed the mount, and therefore the old FD lenses have lost any value, forget about them. After the relatively short life of the FD (about 15 years), Canon released a new type of EF mount, but don't worry, the EF line has about 60 lenses, this should last you a lifetime, so there is plenty to choose from.

EF (Electro-Focus) means that your lens has electronic autofocus, i.e. There is a motor built inside the lens, and the camera only sends commands through contacts on the lens. Actually, all Canon lenses made after 1987 are EF, so this marking is on your...

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The article will talk about a series of zoom lenses that are produced under the wing of Canon. The focal length of all is from 18 to 135 mm. They are designed to work with a crop matrix, so they are only suitable for cameras of this type. The series includes three models. Let's look at all Canon 18-135 mm lenses.

EF-S f/3.5-5.6 IS

The first version that was released was dedicated to the release of a camera from the same manufacturer. We are talking about the EOS 7D camera. The lens is equipped with a special image stabilizer. It has four settings levels. Other Canon 18-135 mm lenses received the same characteristics. For focusing to work, the minimum distance must be 0.45 m. The lens aperture has six blades.

Advantages of the EF-S f/3.5-5.6 IS

Many photographers call this lens universal. Besides this, it is inexpensive. Due to the wide range of focal lengths, you can take good and wide shots. It is suitable for both landscape photography and...

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The first Canon SLR cameras to replace rangefinder cameras appeared in 1959 and had a Canon R mount. In 1964, it was replaced by a Canon FL mount, which in turn gave way to a Canon FD mount in 1971. However, with the advent of the era of autofocus lenses, Canon once again developed a completely new standard in 1987 - Canon EF, which is still relevant today. Unlike Nikon, which has remained faithful to the Nikon F mount since 1959, thereby ensuring the relative compatibility of modern cameras and vintage lenses, Canon began its history from scratch in 1987, and therefore Canon’s principles of compatibility are very simple:

All Canon EF lenses are fully compatible with all Canon EOS cameras, both full-frame and cropped (APS-C).
Canon EF-S lenses are designed for cameras with a crop factor of 1.6 and are not compatible with full frame cameras.
Lenses produced before 1987 are practically useless on modern cameras.

Since 2012, Canon has been releasing APS-C mirrorless cameras (crop factor 1.6) with a Canon EF-M mount, and since 2018, full-frame mirrorless cameras with a Canon RF mount.

All EF-M lenses are fully compatible with all EOS M cameras and are completely incompatible with EOS DSLRs and mirrorless cameras EOS R.
All EF-M lenses are fully compatible with all EOS M cameras and are completely incompatible with EOS DSLRs and EOS M mirrorless cameras.
EF and EF-S lenses are fully compatible with EOS M and EOS R mirrorless cameras with the appropriate adapters.

Basic designations

These parameters are universal and are available for all lenses, regardless of manufacturer.

Focal length The lens is measured in millimeters (for more details, see “Focal length and perspective”). For lenses with a fixed focal length, a single number is indicated, for example, 35mm. For zoom lenses, a range of focal lengths is indicated, for example, 70-300mm.

E.F.(1987) Electro-Focus - Electro-focus. Lenses with a Canon EF mount and a built-in focusing motor. Communication between the lens and the camera is carried out exclusively through electronic contacts. In 1987, this scheme looked very progressive, especially compared to the screwdriver autofocus of Nikon AF lenses. However, Canon paid for this advantage total loss compatibility with your old FD system.

DC(1987) Direct Current - DC motor. Used as a focusing motor in inexpensive Canon EF lenses. Compared to an ultrasonic motor, a DC motor is slower, making it more difficult to photograph fast-moving objects.

USM(1987) Ultrasonic Motor - Ultrasonic motor. Compared to DC motor, USM is faster and quieter. There are two types of ultrasonic motors: ring-type motor and micromotor. The ring-type USM allows manual focusing regardless of whether autofocus is on or off, while the micromotor for manual focusing requires switching to manual mode.

FT-M– Full Time Manual. Constant manual focus. Lenses with an ultrasonic ring-type focusing motor allow you to manually adjust autofocus performance by simply turning the focusing ring without having to switch directly to manual mode.

L– Luxury. Luxury. Expensive professional lenses with a red border. The main advantage of L series lenses lies not so much in high-quality optics (which can be no worse in cheaper lenses), but in mechanical strength and reliability. They are protected from dust and splashes and can withstand being dropped onto rocks without losing their functionality. In addition, L lenses are very large and heavy.

Macro– macro lenses that allow shooting at a scale of 1:1.

I/R– Internal/Rear focusing. Internal/Rear Focus. To focus the lens, movement of an independent group of lenses inside the lens is used. In this case, the dimensions of the lens do not change, and the front lens remains stationary, facilitating the use of polarizing and gradient filters. In addition, such a scheme allows you to reduce the dimensions of the lens, as well as speed up focusing.

Float– A floating optical element that changes its position depending on the focusing distance allows the lens to focus at ultra-close distances without compromising sharpness.

CaF2– Fluorite. Lenses made from fluorite have a low dispersion coefficient, and therefore reduce the severity of secondary (purple-green) chromatic aberrations.

UD– Ultra-low Dispersion glass. Low dispersion glass has a scattering coefficient significantly lower than conventional optical glass. Individual lens elements made from UD glass are designed to reduce secondary chromatic aberration. Due to the lower curvature of the surfaces, lenses made of low dispersion glass are less susceptible to spherical aberrations than lenses made of fluorite.

S-UD– Super Ultra-low Dispersion glass. Ultra-low dispersion glass is even more low-dispersion glass than regular low-dispersion glass. In fact, there is practically no difference between UD and S-UD.

AL– Aspherical Lens. Aspherical lenses included in optical design lenses are used to eliminate spherical aberrations.

TS-E(1991) Tilt-Shift. Tilt-shift lenses allow you to correct perspective distortions by simplified imitation of the movements of a large-format camera. The front of the lens can be moved or tilted within certain limits to correct perspective or to control the focusing plane. TS-E lenses do not have autofocus, and therefore, strictly speaking, are not EF lenses. The letter E in the name TS-E stands for electronic aperture drive.

EF-S(2003) EF-Small. Lenses with a reduced image circle, designed for digital cameras with a sensor with a crop factor of 1.6 (APS-C format). The lenses are not compatible with full-frame EF-S cameras.

EF-M(2012) EF-Mirrorless. Lenses designed for use with Canon EOS M system mirrorless cameras. Not compatible with cameras with an EF mount.

STM(2012) Stepping Motor. The stepper focusing motor is fast and almost silent.

Macro Lite(2017) Built-in flash for macro photography.

RF(2018) Canon RF mount lenses designed for use with Canon EOS R mirrorless cameras. Not compatible with DSLR cameras.

Now let's go to specific example Let's figure out what information you can find out by reading the inscriptions on the lens. Let's take the first lens that comes to hand, and I believe, not without reason, that many of my readers will come across exactly the lens that they purchased along with the camera, i.e. Canon EF-S 18-55mm f/3.5-5.6 IS STM, and let's take a closer look at it. If you have any other lens in your hands, proceed by analogy.

There is an inscription around the front lens element:

CANON ZOOM LENS

EF-S 18-55mm 1:3.5-5.6 IS STM

Ø58mm

CANON ZOOM LENS– reminds the forgetful owner that he has a Canon zoom lens on his camera, and not some other foreign object.

EF-S– name of the system. This lens is designed for Canon EOS cameras with a smaller sensor (APS-C) with a crop factor of 1.6.

18-55mm– range of focal lengths. 18-55mm on a 1.6 crop factor camera will give the same image angle as 29-89mm on a full frame camera. Thus, our lens covers the range from wide-angle to moderately long-angle, which makes it very versatile.

1:3.5-5.6 – aperture. At the wide-angle position (18mm), the minimum aperture value is f/3.5, and at the telephoto position (55mm) – f/5.6. The 18-55mm is not a very fast lens, and its aperture decreases with increasing focal length, but such are all amateur zoom lenses. A large constant aperture ratio would increase their size and cost many times over.

IS– optical image stabilizer. An extremely useful device for handheld photography in low light. For static scenes, it compensates to some extent for the low aperture ratio.

STM– stepper focusing motor.

Ø58– thread diameter for filters. IN in this case diameter is 58 mm.

On the lens body it is written in white and black:

Canon

E.F. S 18-55mm

IMAGE STABILIZER

MACRO 0.25m/0.8ft

Here you can also find a barely visible serial number.

Designations such as EF-S And 18-55mm we have already seen at the end of the lens.

IMAGE STABILIZER- this is the abbreviation decoding IS, whom we also met.

MACRO 0.25m/0.8ft– The minimum focusing distance is 0.25 meters or 0.8 feet. Do not forget that the focusing distance is calculated not from the front lens of the lens, but from the camera matrix. Some Canon lenses have a flower instead of the word MACRO, but it means the same thing.

If you look at the lens from the mount side, you can read:

CANON INC.

MADE IN TAIWAN

Don't be surprised - even Canon is slowly moving its production facilities outside of Japan in order to reduce the cost of production.

I hope that now it will not be difficult for you to make out the markings of any Canon lens.

Thank you for your attention!

Vasily A.

Post scriptum

If you found the article useful and informative, you can kindly support the project by making a contribution to its development. If you didn’t like the article, but you have thoughts on how to make it better, your criticism will be accepted with no less gratitude.

Please remember that this article is subject to copyright. Reprinting and quoting are permissible provided there is a valid link to the source, and the text used must not be distorted or modified in any way.

When marking lenses, manufacturers indicate how numeric values parameters and letter designations some technological solutions for of this device. Let's look at what numerical values can be indicated on the lens and what they mean.

Focal length

One of the main designations is focal length (FL). The angle of view is obtained from the ratio of the focal length to the diagonal of the matrix. According to this parameter, lenses are divided into normal, long-focus and wide-angle. The 35mm film format is common in photography, and it is this parameter that FR leads to. This parameter is called equivalent focal length (EFL). And it is precisely the EGF that is indicated on different lenses instead of the value of the angle of view.

EGF 50 mm - the lens fits the “normal” class;
EGF 28-35mm - wide-angle lenses;
EGF 100-400mm - long-focus lenses;
EFR 80-100mm is a “portrait” lens; it is these lenses that show the best results when shooting a portrait from a distance that provides the desired perspective.

Lens internals

Lens aperture marking

When marking the lens, they can write the focal length value and the aperture ratio corresponding to it.

For example, “50mm F1.4” - for a fixed lens or “7-21mm 1: 2.0-2.8” - for a “zoom”. The first entry indicates a focal length of 50 mm and an aperture ratio of 1.4, and in the second example of an entry for a zoom lens the FR is from 7 mm to 21 mm, and the aperture ratio corresponding to these distances is 2.0 and 2.8.

The lens aperture value shows how many times the brightness of the photographed object will decrease, and not the amount of passing light. Shows how much the lens can convey the actual brightness of the subject.

Fast lenses allow you to take good pictures in low light. The aperture value is determined at the maximum open aperture. This is a permanent property of the optics and does not depend on the current aperture settings. Zoom lenses at different focal lengths have different aperture ratios, since the formula for determining aperture ratio also includes the value of the FR.

There is a distinction between geometric aperture, which depends on the focal length and open aperture. And then there is the effective aperture ratio, which depends on the characteristics of the lens lenses and how much light these lenses can transmit. In practice, you may need a portrait lens with an aperture ratio of about 1:1.8, and other lenses may have a lower aperture ratio (larger number in the denominator). Therefore, there is no need to chase the fastest lenses. Of course, with high-aperture optics, a shorter exposure time is needed, but the photographer can easily solve most problems with a lens with an aperture ratio of 1: 2.8.

Aperture value

To indicate the aperture, write a fraction with the letter F on the lens marking, for example, F/8 instead of the number 8. They can write down the aperture range in addition to the aperture ratio. Typical recording of aperture values for digital point-and-shoot cameras F/2-F/8. This entry should not be confused with the aperture value and the focal length value (the letter F denotes non-focus). The aperture is equal to the ratio of the FR to the size of the aperture opening. In order for more light to pass through the lens, you need to make the aperture hole larger, which means the f-number will be smaller. The smaller the aperture number, the more light will pass through the lens.

Relative hole

The value of the relative hole determines how many times the FR is larger than the hole diameter. The relative aperture is the inverse of the aperture number. The relative opening can be adjusted by the aperture. Rarely encountered in labeling.

Zoom value

Basically, for amateur photography, EGF = 50mm is used, because this value is close to the natural perception of the eye. But it happens that you need to fit more into the frame (landscape), or vice versa, to bring the object closer (portrait, inability to approach the object), then a zoom with an EGF of 35-105, approximately, is used as the main lens. It is this ratio of the zoom at the long end to the value at the short end that is written with the prefix “x” when marking. The higher this value, the lower the aperture ratio, and this is not very good.

Lens letter designations

Lenses are not inferior in price to the cameras themselves, because the quality of the image largely depends on the quality of the lens. Therefore, manufacturers invest a lot of money in the development of new technologies for the production of optics and invent new technical solutions. Each of them has accumulated a lot of its own developments, and each company calls these technological solutions differently. Hence, each company has its own lens designation.

Hello readers! Welcome, Timur Mustaev. Knowledge of abbreviations and the ability to decipher them is useful to any photographer, because they represent valuable information. This is also useful for beginners, who will find it much easier to choose their own equipment and work with it. I have already explained everything, now it’s time to talk about the topic - marking Canon lenses.

In the world of photography, there is a decent amount of different terms and foreign words, often hidden behind abbreviations. The most important ones are already indicated on the camera or lens, and the rest can be found by digging around in detailed description to the product or in my article below.

Fastening. For Canon it is indicated by letters E.F., sometimes added S or M. The differences between them are significant: in the first case, that is, E.F. the lens can work with almost all cameras, including, and in the second, that is EF-S– only with those equipped with APC-S matrices. EF-M The lens is designed for mirrorless cameras.
Aperture property for which he is responsible f, . Depending on her specific meaning optics can have high, medium, or low aperture. The wider the aperture opens, the more light enters, the brighter the frame can be obtained even in the dark. Aperture ratio is highly valued; it largely determines the cost of optics.
Focal length – F, measured in millimeters (mm). The two to three digit number related to this characteristic is one of the main parameters optical device. F can be constant and variable, small and large. Last fact, in turn, divides lenses into standard (portrait) and - each for its own purposes.
Motor type. The internal engine associated with the camera's autofocus may vary. So, USM– a ring motor, which is characterized by speed, accuracy, and noiselessness. It fits most Canon optics. If you have STM, then this is a stepper motor, recommended for shooting videos, as it significantly reduces the accompanying noise and vibration.
Stabilization (IS). If you have it, then you're in luck: you won't be afraid of slight camera shake, which often reduces the clarity and detail of a photo. Availability significantly increases the price of the product.
A.F. And M.F.– enable auto and manual focusing. By the way, the focusing ring itself is located nearby.

We also note a rarer abbreviation, mainly belonging to sophisticated lens models.

Numbers I, II And III. They are not of fundamental importance; they only inform the user about the generation of optics in a particular series.
Macro- a specially designed lens for creating photographs of objects in an enlarged form, in other words - . Such photographic equipment is subject to high demands in terms of lens quality, so their often high price is not surprising.
High quality — L. A category of expensive, luxury lenses equipped with low-distortion glass, they are also considered dust and moisture resistant.
Softfocus– optics that can create softness in the frame. At the moment it is not relevant, since photo editors are capable of any effects, including this one.
TS-E – optical instruments for creative people. Alas, they can only be focused manually; there is no stabilization, but there is the possibility of tilting or shifting it. They are also called Tilt Shift lenses.

To avoid any additional questions and to dilute the theory with a practical part, let’s analyze the lens. We carefully study its name, read from left to right: 1- E.F., type of mount (and compatibility) of optics and camera; 2 — 85mm, fixed focal length, while the lens can be used in a portrait photo shoot; 3 — f/1.8, maximum open aperture indicator, excellent aperture ratio; and 4 – motor type USM.

Goodbye! Dear photographers, visit my blog and subscribe to updates!

All the best to you, Timur Mustaev.

E.F.– this format, introduced back in 1987, refers to a completely electronic lens mount to the camera body. Lenses designated EF are compatible with all EOS film and digital cameras and are capable of working with full-frame 35mm format;
EF-S– The only difference between Canon EF and EF-S lenses is the fact that the latter is designed to work with APS-C sensors, such as that found on the Canon EOS 700D camera. Canon EF-S lenses should not (and in most cases cannot) be mounted on Canon EOS film or digital cameras with a 36x24mm sensor size due to the larger mirror used in these cameras. When attached to such cameras, there is a risk of damage to the mirror when the shutter is released, which may hit the rear element. EF-S lenses are equipped with a special protective element that prevents them from being mounted on full-frame EOS devices;
EF-M is a new lens format that was specifically designed for CanonEOSM mirrorless systems with EF-M mount. Like the EF-S, EF-M lenses are designed for cameras with an APS-C sensor. They can only be used with CanonEOSM system cameras due to their short flange distance (the distance between the lens mount and the film or sensor surface). At the same time, EF and EF-S type lenses can be mounted on the EF-M mount using appropriate adapters, but EF-M lenses cannot be mounted on the EF mount;
FD- This is an old bayonet mount format for manual focusing, used in optics until 1987. Since this mount was not suitable for autofocus, the EOS system with an EF mount was developed. CanonFD lenses have now been discontinued, but the lenses are still used by film camera enthusiasts. There are several modified FD mount lenses that, using special adapters, can be installed on modern EOS EF cameras. An adapter with a special optical element allows you to focus at infinity, while conventional adapters do not allow this;
CHO– lenses identical to FD lenses only without special coating of the front lens (meaning SSC coating, which allows you to cope with side and backlight and achieve excellent contrast);
FL– lenses identical to FD lenses with the inability to work in shutter priority mode.

2) Abbreviation of Canon lenses depending on class and technology:

L– belonging to the “Luxury” line. The L designation denotes top-end, professional lenses with the best optical characteristics and formulas using complex elements. These lenses are created in accordance with the most high standards Canon and are often weather sealed and also feature a wide aperture. The cost of L lenses differs depending on their quality. For example, some lenses can be considered budget, for example the 24-105mm f/4 L lens. Its cost is over $1,100 at the moment, which is certainly not small. But for L-optics this price is more than acceptable. L lenses are easily recognizable thanks to the red ring on the body;
SSC– Super Spectra Coating. Originally invented by Lord Rayleigh in 1886 and later refined by Carl Zeiss, this coating had a huge impact on the development of optics. In effect, this coating minimizes reflections and increases contrast. All modern Canon lenses are multi-coated and only older lenses are marked SSC;
l, ll, lll– Roman numerals indicating the generation of the lens. For example, there are two Canon 24-70mm f/2.8L lenses: the first CanonEF 24-70mm f/2.8L and the second USM CanonEF 24-70mm f/2.8L ll USM. The only difference in the name is the "ll" designation on the second lens, which is actually an updated version of the first lens. Both lenses are professional L-class lenses, but with different optics and prices. Typically, if a lens gets Image Stabilizer (IS), it also means a newer release of the optic;
USM– means that the lens is equipped with a top-end ring ultrasonic motor. This is a fast, quiet and powerful autofocus motor, which also allows you to manually adjust focus at any time. It is used in most modern Canon lenses, from inexpensive prime lenses to expensive L-class lenses;
Micro USM– means that the optics use a simpler and smaller motor. Like its older brother, this motor is fast and quiet and is used in compact lenses with a small number of optical elements. A significant drawback is the fact that Micro USM does not allow manual focus adjustment at any time. But there are exceptions to this rule. One notable lens, the Canon EF 50mm f/1.4 USM, allows full manual focus when the Micro USM motor is engaged. At the same time, it is worth noting that both the presence of a USM motor in the lens and the equipping of the MicroUSM lens with a motor are indicated on the body in the same way, with the letters USM;
STM– Stepper motor designed to minimize vibration and noise when recording video. This motor is gradually making its way into the budget segment of Canon optics. The first lens using STM was EF-M lens 22mm STM. So, all EF-M lenses currently have a stepper motor, and some EF-S lenses have received updated versions with an installed STM motor (for example, EF-S 18-55mm f/3.5-5.6 IS STM). In lenses with an STM motor, the movement of the focus ring is now measured electronically and the data is then sent to the STM motor, which in turn drives the lens system;
A.F.D.– The Arc-Form Drive was the first focusing motor to be used in Canon EF lenses. It is much noisier and slower compared to USM engines. Also worth noting is the slow response, as well as the inability to use manual focusing. If a lens with autofocus does not have motor data indicated on the body, then the optics are equipped with either an AFD motor or a MicroMotor;
MM– this abbreviation stands for Micro Motor, which is essentially a smaller version of the AFD motor. This motor is used only in the cheapest Canon lenses such as the EF-S 18-55mm f/3.5-5.6 IS ll Kit. The motor does not allow you to use manual focusing at any time and produces quite a lot of noise during operation;
PZ– a stand for a zoom lens, which has a special motor for changing the focal length. Perhaps the only lens that uses PZ is the EF 35-80mm f/4-5.6 PZ;
IS– this abbreviation means image stabilization for Canon. Image stabilization refers to technology that moves the optical elements of the lens to counteract shake or shake, and allows for more accurate results with long shutter speeds and static lens positions.

3) Specialized designations for Canon lenses:

Macro– a lens with this designation focuses at relatively short distances and provides a 1:1 magnification;
Compact Macro– similar to regular Macro lenses, but can focus at very close distances (for example the EF 50mm f/2.5 Compact Macro lens). There is a special converter for this lens, which increases the flange distance (the distance between the sensor or film and the front lens of the lens) and makes it possible to magnify 1:1 for this optics (meaning the Canon Life-Size Converter EF);
MP-E– there is only one lens with this designation and that is the Canon MP-E 62mm f/2.8 1-5x Macro. MP-E stands for very high magnification. The lens begins to focus at the distance that is the maximum for most macro lenses. This lens cannot focus at infinity. Instead, the user will have the option of magnification ranging from 1:1 to 5:1;
TS-E– Tilt-shift lenses are used for creative portraits, landscapes, architectural or macro photography. They are exotic and expensive lenses with exclusively manual focus;
DO– lenses using special Diffractive Optics lenses, which bend light more than regular glass. This allows them to be smaller than conventional lenses with the same parameters. A famous example Such optics is the Canon EF 400mm f/4 DO IS USM lens. It, like the L lenses, has impressive build quality, but has a green ring on the body rather than a red one;
Softfocus– as you may have guessed, Softfocus lenses have optical formula, which allows you to get a “softer” picture. Such lenses were very popular several decades ago because they concealed skin imperfections. portrait photography and created a special “soft” frame effect. It is worth noting that such lenses are not particularly popular nowadays, since the soft focus effect can be obtained in post-processing. There is only one Canon EF lens with Softfocus and that is the EF 135mm f/2.8 lens. You can turn off the Softfocus function by turning the corresponding ring on the lens and then the EF 135mm f/2.8 lens will work normally.