Canon RF 50mm F/1.8 STM

Standard prime lens • Digital era

RF The lens is designed for Canon EOS R digital mirrorless cameras.
STM The lens is equipped with stepping motor.

Canon EOS R

35mm digital mirrorless camera

Announced: Sep 2018
Mount: Canon RF
Format: 36 × 24mm
Resolution: 6720 × 4480 - 30 MP
Sensor type: CMOS
Image stabilizer: None

Canon EOS RP

35mm digital mirrorless camera

Announced: Feb 2019
Mount: Canon RF
Format: 35.9 × 24mm
Resolution: 6240 × 4160 - 26 MP
Sensor type: CMOS
Image stabilizer: None

Canon EOS R5

35mm digital mirrorless camera

Announced: Jul 2020
Mount: Canon RF
Format: 36 × 24mm
Resolution: 8192 × 5464 - 45 MP
Sensor type: CMOS
Image stabilizer: Yes

Canon EOS R6

35mm digital mirrorless camera

Announced: Jul 2020
Mount: Canon RF
Format: 36 × 24mm
Resolution: 5472 × 3648 - 20 MP
Sensor type: CMOS
Image stabilizer: Yes

Designed for

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Specification

Announced: November 2020
Production status: In production
Maximum format: 35mm full frame
Mount: Canon RF
Optical design
Diagonal angle of view: 46.8° (35mm full frame)
Lens construction: 6 elements - 5 groups
1 ASPH
Diaphragm mechanism
Number of blades: 7
Focusing
Focusing method: No information
Closest focusing distance: 0.3m
Maximum magnification ratio: 1:4 at the closest focusing distance
Focusing modes: Autofocus, manual focus
Type of autofocus motor: Gear-type Stepping Motor
Focus mode selector: None
Manual focus override in autofocus mode: Determined by camera
Manual focus control: Focusing ring
Image stabilizer
Image Stabilizer (IS): None
Physical characteristics
Weight: 160g
Maximum diameter x Length: Ø69.2×40.5mm
Weather sealing: None
Fluorine coating: None
Accessories
Filters: Screw-in 43mm
Lens hood: Bayonet-type ES-65B (round)

Manufacturer description #1

MELVILLE, N.Y., November 3, 2020 – Canon U.S.A. Inc., a leader in digital imaging solutions, is excited to introduce the compact and lightweight RF70-200mm F4 L IS USM and the RF50mm F1.8 STM, two completely re-designed RF mount lenses with bloodlines to immensely popular EF models that feature new lens formulas and enhanced elements. Canon is also introducing the PIXMA PRO-200 printer, which is ideal for photography students and graphic designers.

“As Canon began to further build out the company’s RF lens portfolio, the goal in mind was to create advanced lenses, for a variety of experience levels, that also featured a sense of familiarity for longtime Canon users,” said Tatsuro “Tony” Kano, executive vice president and general manager of Canon U.S.A.’s Imaging Technologies & Communications Group. “Canon prides itself on being able to uniquely offer both input and output solutions to our customers. We are equally excited to see the images captured with the new lenses, and the prints that are to be created with the new PIXMA PRO-200 printer.”

Canon RF50mm F1.8 STM Lens

Creatives love using a 50mm lens because that focal length is similar to the natural viewpoint of the human field of vision. This perspective allows for the lens to be used in a wide variety of shooting situations, including portraits, landscapes and food photography. What’s more, Canon 50mm f/1.8 lenses have long been a popular tool for both photographers and creators due to their budget-friendly price point, extremely compact and lightweight form factor, and versatility.

The tradition continues with the RF50mm F1.8 STM that, in many ways, is improved over its EF counterpart. The first visually noticeable improvement is the customizable control ring that has become synonymous with RF lenses. The control ring allows photographers to adjust exposure compensation, shutter speed, aperture, or ISO and with a flip of the side switch can adjust focus. The inclusion of a PMo aspherical lens helps to reduce chromatic aberration and provides high-image quality even at the periphery of the image. Additionally, the combination of the lens shape and Super Spectra Coating (SSC) helps to minimize ghosting and flaring.

Manufacturer description #2

Some items like your keys or wallet you just take everywhere you go because you just never know. For anyone with an EOS R series camera, add the RF50mm F1.8 STM lens to that list. As part of the EOS R System, it's nice and compact thanks to its RF mount so you can shoot - and get a great shot - anywhere and anytime. Size isn't all though. As a fixed focal length lens, it lets you be creative with composition and can be used for a wide range of scenes from snapshots to portraits, landscapes to low-light situations and more. Those images will stand out, too, just like you intend whether on social media, or when sharing or printing, thanks to impressive optical features like a PMo aspherical lens to suppress aberrations, Super Spectra coating to reduce flaring and ghosting, and a large f/1.8 aperture for low-light shooting and beautiful bokeh. Pick it up and use it one time and you'll see for yourself, and you won't be able to leave the house without it.

Being bulky or inconvenient to carry is never a concern with the RF50mm F1.8 STM lens. Its compact size makes it appealing to bring on any trip or excursion and is quite handy to have around, too, with its 50mm fixed focal length letting you be creative with composition and because the 50mm focal length is similar to what the actual human eye sees, it provides a great representation to capture impressive portraits, landscapes, food photos and more.

The f/1.8 aperture provides you with a number of benefits and options for your photography, including being able to shoot with faster shutter speeds in low light, helping to decrease the effects of camera shake for a more steady shot, reducing the amount of noise in your image, and the ability to beautifully blur the background or foreground depending on your creative taste.

The RF50mm F1.8 STM lens uses a gear-type stepping motor to provide smooth and quiet autofocus when shooting both still and video, so focusing appears seamless while following a subject with Servo AF, or Movie Servo AF. Focus racks will have clean transitions when repositioning to another subject, or when focusing from foreground to background.

Standard on all RF lenses, the control ring on the lens barrel enables you to adjust numerous settings including shutter speed, aperture, exposure compensation and more. Located towards the front of the lens and effectively adding a third dial to the EOS R and EOS RP, and a fourth dial for EOS R5 and EOS R6 cameras, the control ring has a tactile, easily distinguished surface so you can grasp and make any setting changes quickly. This ring can also be easily switched to function as a focus ring with the focus/control switch located on the side of the lens, so you can adjust the focus to your desired preference.

Since you'll be carrying this lens with you quite often you'll want something that provides great results. The large diameter and short back focus inherent in all RF lenses helps with image quality while a carefully placed single PMo aspherical lens helps to reduce aberrations at the periphery of the image, with lens coatings further assisting by helping to reduce flaring and ghosting, so your images are clear, vivid and inspiring.

You'll have no problem getting that creative, fun and pleasant out-of-focus background blur we all love with the circular 7-blade aperture, so your subject stands out and the background provides a beautiful backdrop that's visually appealing in itself.

Capture amazing shots wherever you are and whatever your subject, even at a close distance of 0.98 ft. at a maximum magnification of 0.25x, making this not just an ideal lens for everyday casual shooting but for more intricate shots like food, flowers and smaller subjects you really want to show off.

Designed to quickly process data, the 12-pin communication system inherent in all RF lenses helps accelerate autofocusing and more, helping to simplify complex operations and provide a quick and reliable user experience.

When combined with an EOS R Series camera with In-Body Image Stabilizer, you can experience the benefits of high-precision 5-axis image stabilization even without Optical Image Stabilization so you can capture amazingly clear and steady results while shooting handheld photos or videos, even in low-light situations like indoors or night scenes, without having to significantly increase the ISO or grab a tripod.

From the editor

Essentially, this lens is the EF 50mm F/1.8 STM model adapted for Canon EOS R series digital mirrorless cameras. The optical design was slightly modified and even received one aspherical element, but the weight and dimensions of both lens are practically the same. As we can see, Canon's general approach to the development of this model has remained the same: to provide amateur photographers with inexpensive but practical compact and lightweight standard lens with fairly fast speed, but without functions found in professional models (complex optical design, internal focusing, floating element system, ultrasonic motor, robust barrel, weather sealing, fluorine coating etc.). However, the fact that this lens is not a professional model does not mean that it cannot deliver excellent image quality. And you will be convinced in this.

Typical application

landscapes, interiors, buildings, cityscapes, portraits, photojournalism, weddings, parties, carnivals, live concerts, street, travel


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Note

Among autofocus lenses designed for 35mm full-frame mirrorless cameras only. Speed of standard and telephoto lenses is taken into account.

Pancake lens

Pancake lenses get their name due to the thin and flat size. The other distinctive features are fixed focal length and light-weight barrel. First pancake lenses appeared in the 1960s and were standard prime lenses based on the famous Tessar design – a brilliantly simple design which was developed by Paul Rudolph in 1902, patented by Zeiss company and provided a good optical performance. With the improvement of optical technologies in the 1970s the optical design of pancake lenses became more complicated and the latest generation has overcome the limitations of traditional designs. As a result, pancake lenses are now also available in wide-angle and short-telephoto variations. Due to the increasing demand for SLR and mirrorless cameras with a compact form factor, pancake lenses are experiencing a second wave of popularity while having reasonable prices, which makes them accessible to a wide range of photographers. Such lenses are especially useful for those who enjoy travel photography.

Travellers' choice

Note

Canon EOS SLR cameras have the shortest flange focal distance of any digital SLR camera, which is 44mm. However, this lens has even shorter flange focal distance of 20mm.

Some manufacturers may offer adapters for this mount in variants with or without magnifying glass. With glass adapter, the image quality will suffer, especially with fast lenses at large apertures (the most common adaptation and use case). With glassless adapter, you will loose the ability to focus at infinity. The choice is yours, however the only right way to adapt this lens is to use a mirrorless camera.

Note

Some manufacturers may offer adapters for this mount in variants with or without magnifying glass. With glass adapter, the image quality will suffer, especially with fast lenses at large apertures (the most common adaptation and use case). With glassless adapter, you will loose the ability to focus at infinity. The choice is yours, however the only right way to adapt this lens is to use a mirrorless camera.

Aperture

The aperture stop is an important element in most optical designs. Its most obvious feature is that it limits the amount of light that can reach the image/film plane. Typically, a fast shutter will require a larger aperture to ensure sufficient light exposure, and a slow shutter will require a smaller aperture to avoid excessive exposure.

A device called a diaphragm usually serves as the aperture stop, and controls the aperture. The diaphragm functions much like the iris of the eye – it controls the effective diameter of the lens opening. Reducing the aperture size increases the depth of field, which describes the extent to which subject matter lying closer than or farther from the actual plane of focus appears to be in focus. In general, the smaller the aperture (the larger the number), the greater the distance from the plane of focus the subject matter may be while still appearing in focus.

The lens aperture is usually specified as an f-number, the ratio of focal length to effective aperture diameter. A lens typically has a set of marked "f-stops" that the f-number can be set to. A lower f-number denotes a greater aperture opening which allows more light to reach the film or image sensor.

The specifications for a given lens typically include the maximum and minimum aperture sizes, for example, f/1.4–f/22. In this case f/1.4 is the maximum aperture (the widest opening), and f/22 is the minimum aperture (the smallest opening). The maximum aperture opening tends to be of most interest, and is always included when describing a lens. This value is also known as the lens "speed", as it affects the exposure time. Lenses with apertures opening f/2.8 or wider are referred to as "fast" lenses. Zoom lenses typically have a maximum relative aperture (minimum f-number) of f/2.8 to f/6.3 through their range. High-end lenses will have a constant aperture, such as f/2.8 or f/4, which means that the relative aperture will stay the same throughout the zoom range. A more typical consumer zoom will have a variable maximum relative aperture, since it is harder and more expensive to keep the maximum relative aperture proportional to focal length at long focal lengths; f/3.5 to f/5.6 is an example of a common variable aperture range in a consumer zoom lens.

Autofocus motor

Micromotors and built-in motors of Nikon, Pentax, Minolta and Sony SLT/SLR cameras provide moderately noisy and acceptably fast autofocus.

With ultrasonic, linear or stepping motor it is possible to achieve very fast and virtually silent autofocus. Moreover, the use of linear or stepping motor ensures smooth continuous focusing which makes lenses with such types of motors ideal for video recording.

The accuracy of autofocus does not depend on type of used autofocus motor but depends on focusing method (contrast or phase detection), autofocus algorithms, lighting conditions and other factors.

Manual focus override in autofocus mode

Allows to perform final focusing manually after the camera has locked the focus automatically. Note that you don't have to switch camera and/or lens to manual focus mode.

Manual focus override in autofocus mode

Allows to perform final focusing manually after the camera has locked the focus automatically. Note that you don't have to switch camera and/or lens to manual focus mode.

Electronic manual focus override is performed in the following way: half-press the shutter button, wait until the camera has finished the autofocusing and then focus manually without releasing the shutter button using the focusing ring.

Image stabilizer

A technology used for reducing or even eliminating the effects of camera shake. Gyro sensors inside the lens detect camera shake and pass the data to a microcomputer. Then an image stabilization group of elements controlled by the microcomputer moves inside the lens and compensates camera shake in order to keep the image static on the imaging sensor or film. The technology allows to increase the shutter speed by several stops and shoot handheld in such lighting conditions and at such focal lengths where without image stabilizer you have to use tripod, decrease the shutter speed and/or increase the ISO setting which can lead to blurry and noisy images.

Focusing method

Photographic lenses carry out focusing using one of the following five methods:

Methods of internal and rear focusing have the following advantages:

Electromagnetic diaphragm control system

Provides highly accurate diaphragm control and stable auto exposure performance during continuous shooting.

Convex protruding front element

The convex front element protrudes from the lens barrel, making it impossible to use filters.

The "Holy Trinity" of lenses

The "Holy Trinity" of lenses refers to a three-lens set that covers a focal length range from the ultra-wide focal length of 14-16mm all the way long to the telephoto focal length of 200mm. The set typically consists of a 16-35mm ultra-wide angle zoom lens, a 24-70mm standard zoom lens and a 70-200mm telephoto zoom lens and usually represents the best constant-aperture zoom lenses in a manufacturer's lineup. The set is designed to cover almost every genre of photography, be it landscapes, architecture, portraits, weddings, sports, travel or even wildlife (with teleconverter). However, it is also expensive, large and heavy.

No focus mode selector

You have to set the automatic or manual focus mode from the camera.

Screw-in lens hood

Fastens to the front thread of the lens barrel.

Slip-on lens hood

Attaches to the lens barrel behind the front rim. A knurled screw tightens a retaining ring, holding the hood firmly to the lens.

Bayonet-type lens hood

Attaches to the bayonet fitting on the front of the lens barrel and locks in place with a twist. After usage, the lens hood can be mounted in reverse for transportation or storage.

Snap-on lens hood

Attaches onto the front of the lens with a spring-type retainer ring. This type of lens hoods is the fastest to attach. After usage, the lens hood can be mounted in reverse for transportation or storage.

Filter access window

The lens hood features a slide-out window which enables rotation of polarizing filter without removing the lens hood.

Aspherical elements

Aspherical elements (ASPH, XA, XGM) are used in wide-angle lenses for correction of distortion and in large-aperture lenses for correction of spherical aberration, astigmatism and coma, thus ensuring excellent sharpness and contrast even at fully open aperture. The effect of the aspherical element is determined by its position within the optical formula: the more the aspherical element moves away from the aperture stop, the more it influences distortion; close to the aperture stop it can be particularly used to correct spherical aberration. Aspherical element can substitute one or several regular spherical elements to achieve similar or better optical results, which allows to develop more compact and lightweight lenses.

Use of aspherical elements has its downsides: it leads to non-uniform rendering of out-of-focus highlights. This effect usually appears as "onion-like" texture of concentric rings or "wooly-like" texture and is caused by very slight defects in the surface of aspherical element. It is difficult to predict such effect, but usually it occurs when the highlights are small enough and far enough out of focus.

Low dispersion elements

Low dispersion elements (ED, LD, SD, UD etc) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture. This type of glass exhibits low refractive index, low dispersion, and exceptional partial dispersion characteristics compared to standard optical glass. Two lenses made of low dispersion glass offer almost the same performance as one fluorite lens.

Low dispersion elements

Low dispersion elements (ED, LD, SD, UD etc) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture. This type of glass exhibits low refractive index, low dispersion, and exceptional partial dispersion characteristics compared to standard optical glass. Two lenses made of low dispersion glass offer almost the same performance as one fluorite lens.

Canon's Super UD, Nikon's Super ED, Pentax' Super ED, Sigma's FLD ("F" Low Dispersion), Sony' Super ED and Tamron's XLD glasses are the highest level low dispersion glasses available with extremely high light transmission. These optical glasses have a performance equal to fluorite glass.

High-refraction low-dispersion elements

High-refraction low-dispersion elements (HLD) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture.

High Index, High Dispersion elements

High Index, High Dispersion elements (HID) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture.

Anomalous partial dispersion elements

Anomalous partial dispersion elements (AD) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture.

Fluorite elements

Synthetic fluorite elements (FL) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture. Compared with optical glass, fluorite lenses have a considerably lower refraction index, low dispersion and extraordinary partial dispersion, and high transmission of infrared and ultraviolet light. They are also significantly lighter than optical glass.

According to Nikon, fluorite easily cracks and is sensitive to temperature changes that can adversely affect focusing by altering the lens' refractive index. To avoid this, Canon, as the manufacturer most widely using fluorite in its telephoto lenses, never uses fluorite in the front and rear lens elements, and the white coating is applied to the lens barrels to reflect light and prevent the lens from overheating.

Short-wavelength refractive elements

High and specialized-dispersion elements (SR) refract light with wavelengths shorter than that of blue to achieve highly precise chromatic aberration compensation. This technology also results in smaller and lighter lenses.

Blue Spectrum Refractive Optics

Organic Blue Spectrum Refractive Optics material (BR Optics) placed between convex and concave elements made from conventional optical glass provides more efficient correction of longitudinal chromatic aberrations in comparison with conventional technology.

Diffraction elements

Diffraction elements (DO, PF) cancel chromatic aberrations at various wavelengths. This technology results in smaller and lighter lenses in comparison with traditional designs with no compromise in image quality.

High refractive index elements

High refractive index elements (HR, HRI, XR etc) minimize field curvature and spherical aberration. High refractive index element can substitute one or several regular elements to achieve similar or better optical results, which allows to develop more compact and lightweight lenses.

Apodization element

Apodization element (APD) is in fact a radial gradient filter. It practically does not change the characteristics of light beam passing through its central part but absorbs the light at the periphery. It sort of softens the edges of the aperture making the transition from foreground to background zone very smooth and results in very attractive, natural looking and silky smooth bokeh.

Lens construction

Lens construction – a specific arrangement of elements and groups that make up the optical design, including type and size of elements, type of used materials etc.

Element - an individual piece of glass which makes up one component of a photographic lens. Photographic lenses are nearly always built up of multiple such elements.

Group – a cemented together pieces of glass which form a single unit or an individual piece of glass. The advantage is that there is no glass-air surfaces between cemented together pieces of glass, which reduces reflections.

Efficiency of Image Stabilizer

The efficiency of image stabilizer is measured in stops and each stop corresponds to a two-times increase of shutter speed. For example, if you are shooting at focal length of 80mm and it is known that the efficiency of image stabilizer is 3 stops, it means that during handheld shooting at such focal length you can use shutter speed of 1/10 second which is exactly 23 times longer than the shutter speed 1/80 second needed to obtain sharp image in sufficient lighting conditions.

Zooming method

The rotary zooming method means that the change of the focal length is achieved by turning the zoom ring and the manual focusing - by turning the separate focusing ring.

The push/pull zooming method means that the change of focal length and the manual focusing is achieved by one and the same ring. The change of focal length happens when the photographer moves the ring towards the mount or backwards and the rotation of the ring leads to change of focus.

Push/pull zooming allows for faster change of focal length, however conventional method based on the rotation of the zoom ring provides more accurate and smooth zooming.

Zoom lock

The lens features a zoom lock to keep the zoom ring fixed. This function is convenient for carrying a camera with the lens on a strap because it prevents the lens from extending.

Power Zoom

The lens features electronically driven zoom mechanism. It provides smoother, more natural zoom movements than you could accomplish by hand.

Filters

Lens filters are accessories that can protect lenses from dirt and damage, enhance colors, minimize glare and reflections, and add creative effects to images.

Lens hood

A lens hood or lens shade is a device used on the end of a lens to block the sun or other light source in order to prevent glare and lens flare. Flare occurs when stray light strikes the front element of a lens and then bounces around within the lens. This stray light often comes from very bright light sources, such as the sun, bright studio lights, or a bright white background.

The geometry of the lens hood can vary from a plain cylindrical or conical section to a more complex shape, sometimes called a petal, tulip, or flower hood. This allows the lens hood to block stray light with the higher portions of the lens hood, while allowing more light into the corners of the image through the lowered portions of the hood.

Lens hoods are more prominent in long focus lenses because they have a smaller viewing angle than that of wide-angle lenses. For wide angle lenses, the length of the hood cannot be as long as those for telephoto lenses, as a longer hood would enter the wider field of view of the lens.

Lens hoods are often designed to fit onto the matching lens facing either forward, for normal use, or backwards, so that the hood may be stored with the lens without occupying much additional space. In addition, lens hoods can offer some degree of physical protection for the lens due to the hood extending farther than the lens itself.

Angle of view

Angle of view describes the angular extent of a given scene that is imaged by a camera. It is used interchangeably with the more general term field of view.

A camera's angle of view depends not only on the lens, but also on the sensor. Digital sensors are usually smaller than 35mm film, and this causes the lens to have a narrower angle of view than with 35mm film, by a constant factor for each sensor (called the crop factor).

This website calculates angles of view of lenses automatically by the following formula: 114.6 * arctan (21.622 / CF * FL),

where:

CF – crop-factor of a sensor,
FL – focal length of a lens.

Mount

A lens mount is an interface — mechanical and often also electrical — between a photographic camera body and a lens. It is confined to cameras where the body allows interchangeable lenses, most usually the rangefinder and SLR cameras.

A lens mount may be a screw-threaded type, a bayonet-type, or a breech-lock (friction lock) type. Modern still camera lens mounts are of the bayonet type, because the bayonet mechanism precisely aligns mechanical and electrical features between lens and body. Screw-threaded mounts are fragile and do not align the lens in a reliable rotational position.

Lens mounts of competing manufacturers (Canon, Nikon, Pentax, Sony etc.) are always incompatible. In addition to the mechanical and electrical interface variations, the flange focal distance from the lens mount to the film or sensor can also be different. These incompatibilities are probably due to the desire of manufacturers to lock in consumers to their brand.

Closest focusing distance

The minimum distance from the focal plane (film or sensor) to the subject where the lens is still able to focus.

Closest working distance

The distance from the front edge of the lens to the subject at the maximum magnification.

Magnification ratio

Determines how large the subject will appear in the final image. A magnification ratio of 1:1 means that the image of the subject formed on the film or sensor will be the same size as the subject in real life. For this reason, a 1:1 ratio is often called "life-size". A lens is not considered to be "true" macro unless it can achieve at least life-size magnification.

Weight

Excluding case or pouch, caps and other detachable accessories (lens hood, close-up adapter, tripod adapter etc.).

Maximum diameter x Length

Excluding case or pouch, caps and other detachable accessories (lens hood, close-up adapter, tripod adapter etc.).

For lenses with collapsible design, the length is indicated for the working (retracted) state.

Fluorine coating

Helps keep lenses clean by reducing the possibility of dust and dirt adhering to the lens and by facilitating cleaning should the need arise. Applied to the outer surface of the front and/or rear lens elements over multi-coatings.

Floating element system

Provides correction of aberrations and ensures constantly high image quality at the entire range of focusing distances from infinity down to the closest focusing distance. It is particularly effective for the correction of field curvature that tends to occur with large-aperture, wide-angle lenses when shooting at close ranges.

Non-retrofocus lens

The lens was designed for use with 35mm film SLR cameras with the mirror locked in the up position. The lens extended into the SLR's mirror box when mounted. Mirror lock-up must be activated prior to mounting the lens; otherwise its rearmost element would be in the way as the mirror flipped up and down during exposure. A separate optical viewfinder had to be mounted on the accessory shoe to confirm angle of view, because when the mirror is in the up and locked position, the subject is no longer visible through the viewfinder.

Format

Format refers to the shape and size of film or image sensor.

35mm is the common name of the 36x24mm film format or image sensor format. It has an aspect ratio of 3:2, and a diagonal measurement of approximately 43mm. The name originates with the total width of the 135 film which was the primary medium of the format prior to the invention of the full frame digital SLR. Historically the 35mm format was sometimes called small format to distinguish it from the medium and large formats.

APS-C is an image sensor format approximately equivalent in size to the film negatives of 25.1x16.7mm with an aspect ratio of 3:2.

Medium format is a film format or image sensor format larger than 36x24mm (35mm) but smaller than 4x5in (large format).

Weather sealing

Weather sealed lenses contain a rubber material which is inserted in between each externally exposed part (manual focus and zoom rings, buttons, switch panels etc.) to ensure it is properly sealed against dust and moisture.

Lenses that accept front mounted filters typically do not have gaskets behind the filter mount. It is recommended to use a filter for complete weather resistance when desired.

Diaphragm type

SLR cameras require stopping down to the chosen aperture immediately before exposure, in order to permit viewing and focusing at full aperture up to the moment the shutter is released.

Historically, there are four different types of diaphragm:

Manual – the diaphragm must be stopped down manually by rotating the detent aperture ring,

Pre-set – the lens has two rings, one is for pre-setting, while the other is for normal diaphragm adjustment. The first ring must be set at the desired aperture, the second ring then should be fully opened for focusing, and turned back for stop down to the pre-set value,

Semi-automatic – the lens features spring mechanism in the diaphragm, triggered by the shutter release, which stops down the diaphragm to the pre-set value. The spring needs to be reset manually after each exposure to re-open diaphragm to its maximum value,

Automatic – the actuating lever in the camera, operated by the shutter release, closes the diaphragm down during the shutter operation. On completion of the exposure, the diaphragm re-opens to its maximum value.

Hybrid IS

The image stabilizer has Hybrid IS technology which corrects not only angle but also shift camera shake, which is more pronounced in close-range shooting when a camera moves parallel to the imaging scene. Hybrid IS dramatically enhances the effects of image stabilization during shooting, including macro shooting, which had proven difficult for conventional image stabilization technologies.

Dynamic IS

The image stabilizer has Dynamic IS technology which especially effective when shooting while walking because it compensates strong camera shake. Dynamic IS activates automatically when the camera is set to movie shooting.

Mode 1

Corrects vertical and horizontal camera shake. Mainly effective for shooting still subjects.

Mode 2

Corrects vertical camera shake during following shots in a horizontal direction. Corrects horizontal camera shake during following shots in a vertical direction.

Mode 2

Corrects vertical camera shake during following shots in a horizontal direction.

Mode 2 (Intelligent OS)

The lens incorporates Intelligent OS with algorithm capable of panning in all directions. In Mode 2, the movements of subjects can be captured with panning effects even when the camera is moved horizontally, vertically, or diagonally — regardless of the position of the lens.

Mode 3

Corrects camera shake only during exposure. During panning shots, corrects camera shake during exposure only in one direction the same as Mode 2. Effective for following fast and irregulary moving subjects.

Panning Detection

The image stabilizer automatically detects panning and then corrects camera shake only in one direction

Tripod Detection

It is often thought that image blur caused by camera shake can be prevented by using a tripod. Actually, however, even using a tripod may result in image blur because of tripod vibration caused by mirror or shutter movement at the time of exposure. The image stabilizer automatically differentiates the frequency of the vibration from that of camera shake, and changes algorithm to correct image blur caused by slight tripod vibration.

VR NORMAL

Corrects vertical and horizontal camera shake. Automatically detects panning and then corrects camera shake only in one direction.

VR ACTIVE

Corrects vertical and horizontal camera shake when shooting from a moving vehicle, or some other unstable position. Panning is not detected.

VR SPORT

Allows a continuous shooting frame rate and release time lag similar to those that are possible when image stabilizer is turned off. Automatically detects panning and then corrects camera shake only in one direction.

VR TRIPOD

It is often thought that image blur caused by camera shake can be prevented by using a tripod. Actually, however, even using a tripod may result in image blur because of tripod vibration caused by mirror or shutter movement at the time of exposure. The image stabilizer automatically differentiates the frequency of the vibration from that of camera shake, and changes algorithm to correct image blur caused by slight tripod vibration.