Tamron 20mm F/2.8 Di III OSD M1:2 F050

Ultra-wide angle prime lens • Digital era

DI III The lens is designed for digital mirrorless cameras.
OSD The lens is equipped with Optimized Silent Drive.
Tamron 20mm F/2.8 Di III OSD M1:2 F050

Features highlight

Extreme AoV
Fast
1 ASPH
3 LD
CFD 0.11m
Macro 1:2
OSD
Compact
Lightweight
WR
FC

Specification

Production details
Announced:October 2019
Production status:In production
Production type:Mass production
Original name:TAMRON 20mm F/2.8 Di III OSD M1:2 F050
Optical design
Focal length:20mm
Speed:F/2.8
Maximum format:35mm full frame
Mount:Sony E
Diagonal angle of view:94.5° (35mm full frame)
70.5° (Sony E APS-C)
Lens construction:10 elements - 9 groups
1 ASPH, 3 LD
Diaphragm mechanism
Number of blades:7
Focusing
Closest focusing distance:0.11m
Maximum magnification ratio:1:2 at the closest focusing distance
Focusing method:Front group linear extension
Focusing modes:Autofocus, manual focus
Manual focus control:Focusing ring
Autofocus motor:Optimized Silent Drive
Focus mode selector:None; focusing mode is set from the camera
Manual focus override in autofocus mode:Determined by the camera
Vibration Compensation (VC)
Built-in VC:-
Physical characteristics
Weight:220g
Maximum diameter x Length:⌀73×64mm
Weather sealing:Water-resistant barrel
Fluorine coating:Front element
Accessories
Filters:Screw-type 67mm
Lens hood:Bayonet-type HF050 (petal-shaped)

*) Source of data: Manufacturer's technical data.

Manufacturer description #1

October 23, 2019, Saitama, Japan – Tamron Co., Ltd. (President & CEO: Shiro Ajisaka), a leading manufacturer of optics for diverse applications, announces the launch of three fixed focal lenses for Sony E-mount full-frame mirrorless cameras: the 20mm F/2.8 Di III OSD M1:2 (Model F050), the 24mm F/2.8 Di III OSD M1:2 (Model F051), and the 35mm F/2.8 Di III OSD M1:2 (Model F053).

Having already produced award-winning zoom lenses* in this mirrorless category, we turned our attention toward fixed focal lenses. When using a fixed focal lens, the photographer must decide the composition based on their distance from the subject. This puts the joy of capturing the image exactly as envisioned and the pure fun of shooting on a different level. The three new models include a 20mm focal length (Model F050) to fully explore the world of ultra wide-angles, a 24mm focal length (Model F051) as the perfect general-purpose wide-angle lens, and the versatile 35mm focal length (Model F053) that is ideal for everyday/every subject use. Developed under the concept of “letting as many as possible learn the joy of fixed focal lenses in a more accessible way,” each lens strikes a balance between gorgeous image rendering and superior operation. We managed to match the same filter size (φ67mm) for all three fixed focal lenses as well as the two previously launched zooms and achieve our aim of compactness. Furthermore, the 20mm, 24mm and 35mm lenses are all capable of focusing very close, to an unprecedented in this category magnification ratio of 1:2. Other features include Moisture-Resistant Construction (for outdoor shooting) and a Fluorine Coating on the front element for easy maintenance and fingerprint removal. They also support various camera features offered by certain Sony cameras, such as Fast Hybrid AF and Eye AF, and offer a multitude of advanced functions to ensure a pleasant shooting experience and fantastic results. This series of highly practical lenses lets photographers enjoy the photographic expression of wide-angle lenses, often regarded as the sweet spot for most photographic pursuits, plus unprecedented light weight and full-blown performance.

* 28-75mm F/2.8 Di III RXD (Model A036) standard zoom and 17-28mm F/2.8 Di III RXD (Model A046).

1. Enhanced close-focusing capability expands lens usefulness and versatility

These fixed focal lenses focus very close. The MOD (Minimum Object Distance) for the 20mm, 24mm and 35mm is 0.11m, 0.12m and 0.15m (4.3, 4.7 and 5.9 inches) respectively. Plus, the maximum magnification ratio for all three is 1:2. This remarkable performance allows users to create compositions that emphasize perspective (closer subjects are larger and distant ones are smaller) and that are unique to wide-angle lenses.

Being able to get in close is one of the most desirable specifications for a wide-angle lens. With dramatic closeup shooting performance for full-frame lenses, the series unleashes an unprecedented level of shooting freedom. Plus, by moving close to the subject, strongly blurred backgrounds are easier to attain.

2. A compact, lightweight 67mm filter diameter system offering excellent portability

Weighing in at 220g (7.8 oz) for the 20mm (Model F050), 215g (7.6 oz) for the 24mm (Model F051) and 210g (7.4 oz) for the 35mm (Model F053), the lenses are exceptionally light, allowing photographers to enjoy shooting comfortably without hesitating about whether to carry the lens. All three lenses combined weigh under 1.5 pounds (645g)! Meanwhile other lenses in Tamron’s lightweight full-frame mirrorless series such as the 28-75mm F/2.8 (Model A036) standard zoom or 17-28mm F/2.8 (Model A046) ultra wide-angle zoom make the perfect companions to broaden the range of shooting possibilities.

As testament to their compactness, all three new models feature the same 67mm filter diameter as Tamron’s zoom lenses for full-frame mirrorless cameras. This significantly reduces cost and packing space when working with PL, ND and other filters. Even the front lens caps are the same size, eliminating the hassle of sorting caps when switching lenses. These features combine to produce a highly convenient and mobile system that adds more fun to photography.

3. Superb high-resolution performance that matches the latest high-resolution image sensors

The sophisticated optical formula created with the latest lens design technologies boasts exceptionally high rendering performance from edge to edge thanks to the optimal arrangement of LD (Low Dispersion) and GM (glass-molded aspherical) lens elements. Any remaining minor distortions sometimes common in wide-angle lenses are corrected using in-camera functions. Additionally, Tamron’s legendary BBAR (Broad-Band Anti-Reflection) Coating effectively reduces ghosting and flare. With excellent resolving power achieved through uncompromising optical performance and camera-based distortion correction, these lenses can be used with complete confidence for a wide range of applications from casual family snaps to serious professional photography.

4. Consistent 64mm (2.5 in) overall length facilitates ease-of-use

All three lenses are the same length: 64mm (2.5 in). Achieving excellent balance with Sony E-mount cameras, these compact lenses employ a front element extension system but are designed to maintain the same exterior length during focusing operations. Therefore, there is less chance of an extended front element accidentally coming into contact with a subject during closeup shooting. And optional manual focusing is easier because the focus ring is positioned toward the front of the lens within natural reach of the thumb and index finger.

5. Silent autofocus driven by OSD (Optimized Silent Drive) DC motor

The AF drive system employs an OSD to ensure quiet operation. In comparison to conventional AF types with built-in DC motors, Tamron was able to greatly reduce the drive noise as well as vastly improve AF performance and speed. The lower ambient noise level is sure to be appreciated by video shooters. Overall, this fixed focal lens series provides superlative AF precision for exact focus even when shooting moving subjects, as well as outstanding accuracy and tracking capability. Additionally, this fixed focal series supports various AF features offered by certain Sony cameras, including Fast Hybrid AF, Eye AF, and Direct Manual Focus (DMF) to ensure a pleasant shooting experience.

6. Moisture-Resistant Construction and Fluorine Coating

Environmental seals are located at the lens mount area and other critical locations to prevent infiltration of moisture and/or rain drops and afford Moisture-Resistant Construction. This feature provides an additional layer of protection when shooting outdoors under adverse weather conditions. Also, the front surface of the lens element is coated with a protective fluorine compound that has excellent water- and oil-repellant qualities. The lens surface is easier to wipe clean and is less vulnerable to the damaging effects of dirt, moisture or oily fingerprints, allowing for much easier maintenance. These protective features are keenly important for lenses that allow you to get in close to a subject.

7. Compatible with main camera-specific features and functions

All three of Tamron’s new fixed focal lenses are compatible with many of the advanced features that are specific to certain mirrorless cameras. These include the following:

  • Fast Hybrid AF
  • Eye AF
  • Direct Manual Focus (DMF)
  • In-camera lens correction (shading, chromatic aberration, distortion)
  • Camera-based lens unit firmware updates

* Features vary by camera. Please consult your camera’s instruction manual for details.

Manufacturer description #2

The 20mm F/2.8 Di III OSD M1:2 (Model F050) is fast handling and packs expressive power that is the signature of fixed focal lenses. It’s the ideal first ultra wide-angle lens for any photographer. It is designed exclusively for mirrorless cameras. Light weight and compact, the Model F050 is extremely portable, ideal for situations where you need to travel light. The Model F050 is a creative tool that dynamically captures scenery by maximizing the perspective unique to ultra wide-angle lenses. The incredibly short 0.11m (4.3 in) MOD (Minimum Object Distance) makes it possible to get closer to your subjects than you’d ever imagined. In addition to the F/2.8 aperture, the Model F050 is constructed using special glass materials including LD (Low Dispersion) and GM (Glass Molded Aspherical) lens elements effectively arranged to quash aberrations. The Model F050 provides outstanding optical performance across the entire frame, and delivers a sharp image, right down to the texture of the subject. With Moisture-Resistant Construction and dirt-resistant Fluorine Coating, photographers can shoot confidently outdoors. If you can own only one ultra wide-angle, the Model F050 should be your first choice.

One of the key features that makes this lens so exciting is its amazing ability to shoot close-ups. With this lens, you can get closer to an object than you’d ever imagined. At the 0.11m (4.3 in) MOD, the lens achieves its maximum magnification ratio of 1:2. You’ll never again be frustrated because you cannot get close to an object while shooting. This remarkable performance allows users to create compositions that exploit dramatic perspective (closer subjects are larger, and distant ones are smaller) and that are unique to wide-angle lenses. By getting close to an object, you can produce a one-of-a-kind photo and leverage the beautifully blurred background bokeh.

Take it with you anywhere. This lens travels as well as it performs. And because it’s matched to lightweight full-frame mirrorless cameras, your entire system becomes light, fast and nimble. It has a very compact body, weighing just 220g (7.8 oz) and an overall length of 64mm (2.5 in). It’s comfortably portable, highly maneuverable and amazingly easy to use and compose. Because the overall length does not change when focusing, you can get as close to an object as you need to without fear of accidentally bumping the front element. The lens has the same 67mm filter diameter as the other members of the series of Tamron high-speed lenses for Sony E-mount cameras. So you can swap filters (like polarizers), lens caps and other accessories for convenience. Who says great things can’t come in small packages?

This lens provides outstanding optical performance and overall image quality, characteristics relentlessly demanded from a prime, fixed focal lens. The expert arrangement of the LD and GM specialized glass elements greatly controls aberrations, including chromatic aberrations. Tamron’s proprietary BBAR (Broad-Band Anti-Reflection) Coating reduces ghosting and flare, which can otherwise occur when taking a photo against the sun. Moreover, leveraging your camera body’s features* it delivers, throughout the frame, high resolution performance that maximizes the benefits of the latest high-megapixel cameras. Whether shooting on the street, full-scale landscapes or architectural photography, this lens delivers exceptionally crisp, colorful and beautiful images and helps you fulfill your creative ambitions.

* When shooting with the camera’s lens correction function enabled.

The AF drive employs a newly developed OSD (Optimized Silent Drive) to ensure silent operation. Operating noise has been appreciably reduced thanks to a revamped and optimized AF unit. The precision and speed of autofocusing are increased to ensure accurate focus even when tracking constantly moving subjects.

For greater protection when shooting outdoors, leak-resistant seals throughout the lens barrel help protect your equipment.

The front surface of the lens element is coated with a protective fluorine compound that is water- and oil-repellant. The lens surface is easier to wipe clean and is less vulnerable to the damaging effects of dirt, dust, moisture and fingerprints.

A 7-blade diaphragm is configured to retain a smooth, circular-shaped aperture opening even when stopped down by two stops from the wide-open aperture. This produces a smooth-edged bokeh in background light spots and avoids rugged aperture geometry.

The application of BBAR (Broad-Band Anti-Reflection) Coating for suppressing reflections on lens element surfaces minimizes unwanted flare and ghosting to deliver sharp, crisp, high-contrast images.

This lens is just one of many Tamron lenses for Sony E-mount cameras. Throughout the lineup you’ll find creative tools that help you enjoy the world of mirrorless cameras and a broader range of photographic possibilities. Small and light weight (the perfect match for mirrorless cameras) they are definitively portable and can easily be all carried together as a complete set that’s ready for every situation. For convenience sake, all of the lenses in the series have the same 67mm filter diameter. You can share the use of a single polarizing (or other) filter and avoid the aggravation of searching through lens caps when changing lenses. Built with convenience and ease-of-use in mind, you’ll be attracted by the compact size and thoroughly dazzled by the outstanding performance.

Typical application

landscapes, interiors, buildings, cityscapes, travel

Notes and recommendations

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Tamron 20mm F/2.8 Di III OSD M1:2 F050

Tamron 20mm F/2.8 Di III OSD M1:2 F050
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35mm full frame

43.27 24 36
  • Dimensions: 36 × 24mm
  • Aspect ratio: 3:2
  • Diagonal: 43.27mm

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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.

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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.

Optimized Silent Drive

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.

Original name

Lens name as indicated on the lens barrel (usually on the front ring). With lenses from film era, may vary slightly from batch to batch.

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).

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.

As the focal length changes, the angle of view also changes. The shorter the focal length (eg 18mm), the wider the angle of view. Conversely, the longer the focal length (eg 55mm), the smaller the angle of view.

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

This website does not use the angles of view provided by lens manufacturers, but calculates them 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 camera body and a lens.

A lens mount may be a screw-threaded type, a bayonet-type, or a breech-lock type. Modern camera lens mounts are of the bayonet type, because the bayonet mechanism precisely aligns mechanical and electrical features between lens and body, unlike screw-threaded mounts.

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.

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.

Flange focal distance

The flange focal distance (FFD), sometimes called the "flange back", is the distance from the mechanical rear end surface of the lens mount to the focal plane.

Focal length

The focal length is the factor that determines the size of the image reproduced on the focal plane, picture angle which covers the area of the subject to be photographed, depth of field, etc.

Speed

The largest opening or stop at which a lens can be used is referred to as the speed of the lens. The larger the maximum aperture is, the faster the lens is considered to be. Lenses that offer a large maximum aperture are commonly referred to as fast lenses, and lenses with smaller maximum aperture are regarded as slow.

In low-light situations, having a wider maximum aperture means that you can shoot at a faster shutter speed or work at a lower ISO, or both.

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. For example, 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".

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.

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.

Fixed focus

There is no helicoid in this lens and everything is in focus from the closest focusing distance to infinity.

Overall linear extension

The entire lens optical system moves straight backward and forward when focusing is carried out. This is the simplest type of focusing used mainly in wide-angle and standard prime lenses. It has the advantage of introducing relatively little change in aberrations with respect to change in focusing distance. With telephoto and super telephoto lenses this method becomes less beneficial in terms of operability because of the increased size and weight of the lens system.

Front group linear extension

The rear group remains fixed and only the front group moves straight backward and forward during focusing. This method is primarily used in zoom lenses and allows to design comparatively simple lens construction, but also places restrictions on zoom magnification and size reduction.

Front group rotational extension

The lens barrel section holding the front lens group rotates to move the front group backward and forward during focusing. This method of focusing is also used only in zoom lenses.

Internal focusing (IF)

Focusing is performed by moving one or more lens groups positioned between the front lens group and the diaphragm.

Methods of internal and rear focusing have the following advantages:

Rear focusing (RF)

Focusing is performed by moving one or more lens groups positioned behind the diaphragm.

Methods of internal and rear focusing have the following advantages:

Number of blades

As a general rule, the more blades that are used to create the aperture opening in the lens, the rounder the out-of-focus highlights will be.

Some lenses are designed with curved diaphragm blades, so the roundness of the aperture comes not from the number of blades, but from their shape. However, the fewer blades the diaphragm has, the more difficult it is to form a circle, regardless of rounded edges.

At maximum aperture, the opening will be circular regardless of the number of blades.

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.

Weather sealing

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.

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.

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.