Pentax K-50

APS-C AF digital SLR camera

Specification

Production details:
Announced:June 2013
System: Pentax K APS-C (2003)
Format:
Maximum format:APS-C
Imaging sensor:23.7 × 15.7mm CMOS sensor
Resolution:4928 × 3264 - 16 MP
Crop factor:1.52x
Sensor-shift image stabilization:Yes
Mount and Flange focal distance:Pentax K [45.5mm]
Shutter:
Type:Focal-plane
Model:Electronically controlled
Speeds:30 - 1/6000 + B
Exposure:
Exposure metering:Through-the-lens (TTL), open-aperture
Exposure modes:Programmed Auto
Aperture-priority Auto
Shutter-priority Auto
Manual
Physical characteristics:
Weight:590g
Dimensions:129x96.5x70mm

Manufacturer description #1

Denver, CO (June 12, 2013) — PENTAX RICOH IMAGING AMERICAS CORPORATION today introduced the PENTAX K-50 DSLR featuring advanced functionality beyond its mid-level classification. Ideal for photographers looking to transcend traditional DSLR offerings, the PENTAX K-50 combines a uniquely advanced feature set with a consumer-friendly price tag and 120 color combinations to meet an important additional demand of the creative consumer: personal style.

Rivaling many cameras higher in class, the K-50 boasts a long list of advanced specifications not found in other mid-level DSLRs. Beginning with its 81weather seals, the K-50 incorporates PENTAX’s long-standing heritage of weather-resistant products making cameras that extend shooting environments to wet, rainy or snowy conditions. Building on this leading advantage, the K-50 features high-speed continuous shooting at approximately six frames per second, super-high-sensitivity shooting at ISO settings up to 51200 and high-precision SAFOX IXi+ autofocus with accurate subject tracking, guaranteeing crisp images even when in low-light or with a fast moving subject. Additionally, the K-50’s 100% field of view viewfinder, innovative shake reduction system, four optional interchangeable focusing screens and a fast shutter with the ability to shoot at speeds up to 1/6000 of a second enable photographers to push the boundaries of high-speed shooting while providing total confidence that their vision is framed accurately and captured in complete focus. And, with new Eye-fi SD card compatibility built in photo and video sharing a breeze! Users can enable automatic transmission of images and video to a smartphone for rapid sharing and even select their favorite images and resize them before transmission.

The K-50 is available in 120 brilliant and eye-catching color combinations and sets a new standard in the customization of electronics. PENTAX’s Color to Order™ system takes advantage of a newly architected supply chain management system that is built to empower consumers to design the product they want.

“The K-50 introduces features that raise the bar in the mid-level DSLR class,” said Jim Malcolm, executive vice president, PENTAX RICOH IMAGING AMERICA. “Not only do the hardware and software specs outclass competitors, the Color to Order system is an industry first making it a truly unique offering among a sea of similarity.”

PENTAX has also strengthened its weather-sealed lens lineup with the debut of two new lenses; the smc PENTAX-DA L 18-55mm F3.5-5.6AL WR, and smc PENTAX-DA L 50-200 F4-5.6ED WR. The addition of these two lenses expands PENTAX’s extensive line of weather-sealed lenses which offer a wide variety of focal lengths and shooting perspectives ensuring there is a lens appropriate for many different shooting and weather scenarios.

Also introduced today is the PENTAX K-500, an entry-level DSLR that augments PENTAX’s DSLR lineup by including advanced features uncommon to the entry-level class. Ideal for families and casual photographers with rigorous demands, the K-500 features a 16 megapixel APS-C CMOS image sensor, fast continuous shooting, high sensitivity shooting up to ISO 51200, 100% field of view, in-body shake reduction, and an advanced auto focus module. Operating on four AA batteries, the K-500 guarantees ultimate flexibility and accessibility to a power source when travelling or in remote locations. In addition, the K-500’s wide selection of simple user-modes and creative tools enable limitless personalized expressions while its intuitive ergonomics and menu layout make the K-500 approachable and comfortable to use.

Both the K-50 and K-500 are built around PENTAX’s acclaimed K-mount system. Thanks to the lasting commitment PENTAX has made to the K-mount photographers are able to use any of the 25 million K-mount lenses that have been manufactured over the life of the mount. Access to this wide a selection is unparalleled and opens up many new perspectives for photographers encouraging boundless creativity.

Manufacturer description #2

June 13, 2013 - PENTAX RICOH IMAGING COMPANY, LTD. is pleased to announce the launch of the PENTAX K-50 digital SLR camera. Developed as the model to feature a weather-resistant, dustproof construction,* this compact, lightweight camera offers outstanding operability and maneuverability, with many of the advanced shooting features found only in upper-class models.

The PENTAX K-50 boasts outstanding basic specifications that rival many upper-class models, including high-speed continuous shooting at approximately six images per second, super-high-sensitivity shooting at ISO 51200, and high-precision AF with accurate tracking of moving subjects. This means that beginning digital SLR users and casual family photographers can enjoy high-quality digital photography with very little effort. The K-50 also features a weather-resistant, dustproof construction to assure solid performance under demanding outdoor conditions, and also to reduce the need for maintenance. It even provides a wide range of advanced shooting features, such as full HD movie recording and a selection of creative tools such as digital filters, to accommodate various shooting requirements. It can be powered by easy-to-obtain AA-size batteries,** in addition to the standard lithium-ion battery.

Launched simultaneously with the K-50 camera body, two lens kits feature simplified weather-resistant lenses — the smc PENTAX-DA L 18-55mm F3.5-5.6AL WR, and the smc PENTAX-DA L 50-200 F4-5.6ED WR — to enhance the reliability and dependability of the K-50 imaging system.

The standard K-50 model offers a choice of three body colors: black, white and pink.

* Based on PENTAX research, as of June 1, 2013.

** The optional D-BH109 AA Battery Holder is required for AA-battery operation.

Major Features

1. High-resolution, super-high-sensitivity shooting at ISO 51200

The K-50 features the state-of-the-art CMOS image sensor with a large image-capturing area measuring 23.7mm by 15.7mm, to assure high-speed image data readout. This image sensor is coupled with PRIME M — the same high-performance imaging engine incorporated in upper-class models — to deliver super-high-resolution, rich-gradation digital images with approximately 16.28 effective megapixels. The K-50 also offers super-high-sensitivity shooting at a top sensitivity of ISO 51200, allowing the photographer to handhold the camera for beautiful nighttime snapshots.

2. Dependable weather-resistant, dustproof body

Thanks to the 81 seals set in its compact, lightweight, portable body, the K-50 is built to be weather-resistant, dustproof and cold-resistant, even at temperatures as low as -10°C. This means that the K-50 can be taken along on outdoor activities such as camping, mountaineering and sports, for the joy of high-quality digital SLR photography without worrying about weather conditions. Its compact, functional body is carefully contoured with delicate curves, assuring that even a photographer with a small hand will have a firm grip of the camera.

3. Innovative SR mechanism

The PENTAX-developed SR (Shake Reduction) mechanism effectively compensates the adverse effect of camera shake to deliver sharp, blur-free images, even under shake-prone conditions such as when using a telephoto lens, shooting in the dark without flash illumination, or taking landscapes at twilight. This innovative mechanism works with almost all PENTAX interchangeable lenses — even those developed for film-format cameras.*** Thanks to the SR mechanism’s flexible design, which tilts the image sensor unit in all directions, the K-50 offers several useful features to assist the photographer during shooting, including an Automatic Horizon Correction function to assure high-precision image framing and effortless adjustment of horizontal alignment; a Composition Adjustment function to allow minute adjustment of image alignment both to horizontal and vertical directions, as well as slant-wise rotation; and an ASTRO TRACER mode to simplify astronomical photography in combination with the optional O-GPS1 GPS Unit.

*** Lenses compatible with this mechanism: PENTAX K, KA, KAF, KAF2 and KAF3mount lenses; screw-mount lenses (with an adapter); and 645 and 67system lenses (with an adapter). Some functions may not be available with certain lenses.

4. High-precision autofocus with SAFOX IXi+ AF module

The K-50 features the state-of-the-art SAFOX IXi+ AF sensor module, which assures responsive, high-precision autofocus operation with 11 sensors (including nine cross-type sensors in the middle). It also features a spotbeam projector to assist AF operation at poorly lit locations. Its select-area expansion function keeps the sensor module tracking a moving subject, even when it moves out of a pre-assigned auto-tracking area, by assessing the distance data collected by neighboring focus sensors. This means not only greatly improved accuracy and speed of detecting moving subjects during autofocus operation, but also the enhanced auto-tracking performance of moving subjects when using a telephoto lens.

5. High-speed continuous shooting

When shooting sports, stage performances or wildlife, the K-50's high-speed continuous shooting function comes in handy. It allows the photographer to record active, fast-moving subjects in a series of images, at a maximum speed of approximately six images per second**** (in the JPEG recording format).

**** using the D-LI109 Rechargeable Lithium-ion Battery. When using with AA batteries, the camera can capture approximately five images per second.

6. High-quality movie recording

The K-50 captures high-resolution, full HD movie clips (1920 x 1080 pixels) in the H.264 recording format, with a choice of frame rate (30, 25 or 24 frames per second). It even comes with creative image-processing tools***** like Custom Images and useful movie-recording features like an interval movie recording function, for the production of more personalized movies.

***** The frame rate may vary when nonstandard image processing is required.

7. Optical finder with approximately 100% field of view

Despite a compact body common to all entry-class models, the K-50 features a glass prism finder with nearly 100% field of view and approximately 0.92-times magnification (with a 50mm F1.4 lens at infinity) to cover the entire field of view for easy focusing and framing. Since it delivers a clear view of the subject even in bright sunshine and eliminates parallax and time lag in the viewfinder image, the K-50 responds efficiently and reliably to demanding applications and subjects, such as landscapes requiring delicate, high-precision framing, and sports scenes where the timing of shutter release is critical. The infocus point is indicated as a red point in the viewfinder for at-a-glance confirmation.

8. Effortless, user-friendly Auto Picture and Scene modes

The PENTAX-original Auto Picture mode automatically selects the most appropriate shooting mode for a given subject or scene from Portrait, Landscape, Macro and other distinctive shooting modes. Since the K-50 sets all vital camera settings — including shutter speed, aperture, white balance, saturation, contrast and sharpness — the photographer can concentrate on image composition and shutter opportunity. The K-50 also offers 19 Scene modes, including Night Scene Portrait, Pet and Backlight Silhouette, to simplify the photographing of subjects and scenes that could be too complicated or demanding for entry digital SLR photographers, by optimizing all camera settings with a simple choice of the corresponding icon on the camera's LCD monitor.

9. A selection of image-processing tools for creative, personalized expression

The K-50’s custom image function allows the user to easily and quickly select the desired finishing touch for a particular image, with a choice of 11 custom images. These include Bleach Bypass to create a dramatic visual effect used in motion pictures, and Cross Process to produce fanciful, eye-catching images with dramatic colors. The K-50 also provides 19 distinctive digital filters to add distinctive visual effects to captured images and produce creative, artistic images without the need for a computer. The user can even explore new creative possibilities by applying multiple filters to a single image.

10. Choice of two power sources

In addition to the standard rechargeable lithium-ion battery capable of capturing approximately 480 images with a single recharge,****** the K-50 can also be powered by four AA-size batteries using the optional D-BH109 AA Battery Holder. Since AA-size batteries can be easily obtained almost anywhere around the world, there’s no worry about battery shortages, even when on the road.

****** Under testing conditions prescribed by PENTAX, using the D-LI109 Rechargeable Lithium-ion Battery with no flash discharges.

11. Other features

  1. Large, wide-view 3.0-inch LCD monitor with approximately 921,000 dots
  2. 77-segment multi-pattern metering system for extra-accurate light measurement
  3. DR (Dust Removal) mechanism to shake dust from the surface of the CMOS image sensor
  4. Digital level for extra-accurate image composition
  5. PENTAX-designed Hyper control system to assure flexible, unfailing response to the photographer’s creative intentions
  6. RAW data retrieve function to save an original raw data of a just-recorded JPEG-format image
  7. RAW/Fx button for single-action switching of image file format, as well as for assignment and instant recall of a specific function
  8. Compatibility with Eye-Fi wireless LAN SD memory cards
  9. SILKYPIX Developer Studio 3.0 LE for PENTAX RICOH IMAGING(RAW-data processing engine developed by Ichikawa Soft Laboratory) included, together with the K-50’s in-body RAW data processing capability

[Overview of smc PENTAX-DA L 18-55mmF3.5-5.6AL WR lens]

This standard zoom lens covers focal lengths from 27.5mm wide angle to 84mm moderate telephoto (in the 35mm format). Thanks to the incorporation of high-performance aspherical and super-low-dispersion glass optical elements in its optics, it assures outstanding image resolution and remarkable brightness, even at the edges, while effectively compensating various aberrations.

[Overview of smc PENTAX-DA L 50-200mmF4-5.6ED WR lens]

This telephoto zoom lens covers focal lengths from 76.5mm moderate telephoto to 307mm super telephoto (in the 35mm format). With the incorporation of extra-low-dispersion (ED) glass optical elements, it assures excellent description of the subject in various telephoto applications, including portraiture, sports/action and landscape, while effectively compensating chromatic aberration over the entire zoom range.

[A feature common to both lenses]

Both lenses feature a simplified weather-resistant construction, which prevents the intrusion of water into the lens barrel. By mounting one of these lenses on the K-50 camera body, the user creates a highly durable, dependable digital imaging system, even when shooting in the rain, mist or spray.

Similar cameras (4)

APS-C • Auto focus • Digital • Singe-lens reflex • Pentax K mount

Model Shutter Metering Modes Year
Samsung GX-10 E, 1/4000 TTL • OA PASM 2006
Samsung GX-1L E, 1/4000 TTL • OA PASM 2006
Samsung GX-1S E, 1/4000 TTL • OA PASM 2006
Samsung GX-20 E, 1/4000 TTL • OA PASM 2008
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Chromatic aberration

There are two kinds of chromatic aberration: longitudinal and lateral. Longitudinal chromatic aberration is a variation in location of the image plane with changes in wave lengths. It produces the image point surrounded by different colors which result in a blurred image in black-and-white pictures. Lateral chromatic aberration is a variation in image size or magnification with wave length. This aberration does not appear at axial image points but toward the surrounding area, proportional to the distance from the center of the image field. Stopping down the lens has only a limited effect on these aberrations.

Spherical aberration

Spherical aberration is caused because the lens is round and the film or image sensor is flat. Light entering the edge of the lens is more severely refracted than light entering the center of the lens. This results in a blurred image, and also causes flare (non-image forming internal reflections). Stopping down the lens minimizes spherical aberration and flare, but introduces diffraction.

Astigmatism

Astigmatism in a lens causes a point in the subject to be reproduced as a line in the image. The effect becomes worse towards the corner of the image. Stopping down the lens has very little effect.

Coma

Coma in a lens causes a circular shape in the subject to be reproduced as an oval shape in the image. Stopping down the lens has almost no effect.

Curvature of field

Curvature of field is the inability of a lens to produce a flat image of a flat subject. The image is formed instead on a curved surface. If the center of the image is in focus, the edges are out of focus and vice versa. Stopping down the lens has a limited effect.

Distortion

Distortion is the inability of a lens to capture lines as straight across the entire image area. Barrel distortion causes straight lines at the edges of the frame to bow toward the center of the image, producing a barrel shape. Pincushion distortion causes straight lines at the edges of the frame to curve in toward the lens axis. Distortion, whether barrel or pincushion type, is caused by differences in magnification; stopping down the lens has no effect at all.

The term "distortion" is also sometimes used instead of the term "aberration". In this case, other types of optical aberrations may also be meant, not necessarily geometric distortion.

Diffraction

Classically, light is thought of as always traveling in straight lines, but in reality, light waves tend to bend around nearby barriers, spreading out in the process. This phenomenon is known as diffraction and occurs when a light wave passes by a corner or through an opening. Diffraction plays a paramount role in limiting the resolving power of any lens.

Doublet

Doublet is a lens design comprised of two elements grouped together. Sometimes the two elements are cemented together, and other times they are separated by an air gap. Examples of this type of lens include achromatic close-up lenses.

Dynamic range

Dynamic range is the maximum range of tones, from darkest shadows to brightest highlights, that can be produced by a device or perceived in an image. Also called tonal range.

Resolving power

Resolving power is the ability of a lens, photographic emulsion or imaging sensor to distinguish fine detail. Resolving power is expressed in terms of lines per millimeter that are distinctly recorded in the final image.

Vignetting

Vignetting is the darkening of the corners of an image relative to the center of the image. There are three types of vignetting: optical, mechanical, and natural vignetting.

Optical vignetting is caused by the physical dimensions of a multi-element lens. Rear elements are shaded by elements in front of them, which reduces the effective lens opening for off-axis incident light. The result is a gradual decrease of the light intensity towards the image periphery. Optical vignetting is sensitive to the aperture and can be completely cured by stopping down the lens. Two or three stops are usually sufficient.

Mechanical vignetting occurs when light beams are partially blocked by external objects such as thick or stacked filters, secondary lenses, and improper lens hoods.

Natural vignetting (also known as natural illumination falloff) is not due to the blocking of light rays. The falloff is approximated by the "cosine fourth" law of illumination falloff. Wide-angle rangefinder designs are particularly prone to natural vignetting. Stopping down the lens cannot cure it.

Flare

Bright shapes or lack of contrast caused when light is scattered by the surface of the lens or reflected off the interior surfaces of the lens barrel. This is most often seen when the lens is pointed toward the sun or another bright light source. Flare can be minimized by using anti-reflection coatings, light baffles, or a lens hood.

Ghosting

Glowing patches of light that appear in a photograph due to lens flare.

Retrofocus design

Design with negative lens group(s) positioned in front of the diaphragm and positive lens group(s) positioned at the rear of the diaphragm. This provides a short focal length with a long back focus or lens-to-film distance, allowing for movement of the reflex mirror in SLR cameras. Sometimes called an inverted telephoto lens.

Anastigmat

A photographic lens completely corrected for the three main optical aberrations: spherical aberration, coma, and astigmatism.

By the mid-20th century, the vast majority of lenses were close to being anastigmatic, so most manufacturers stopped including this characteristic in lens names and/or descriptions and focused on advertising other features (anti-reflection coating, for example).

Rectilinear design

Design that does not introduce significant distortion, especially ultra-wide angle lenses that preserve straight lines and do not curve them (unlike a fisheye lens, for instance).

Focus shift

A change in the position of the plane of optimal focus, generally due to a change in focal length when using a zoom lens, and in some lenses, with a change in aperture.

Transmittance

The amount of light that passes through a lens without being either absorbed by the glass or being reflected by glass/air surfaces.

Modulation Transfer Function (MTF)

When optical designers attempt to compare the performance of optical systems, a commonly used measure is the modulation transfer function (MTF).

The components of MTF are:

The MTF of a lens is a measurement of its ability to transfer contrast at a particular resolution from the object to the image. In other words, MTF is a way to incorporate resolution and contrast into a single specification.

Knowing the MTF curves of each photographic lens and camera sensor within a system allows a designer to make the appropriate selection when optimizing for a particular resolution.

Veiling glare

Lens flare that causes loss of contrast over part or all of the image.

Anti-reflection coating

When light enters or exits an uncoated lens approximately 5% of the light is reflected back at each lens-air boundary due to the difference in refractive index. This reflected light causes flare and ghosting, which results in deterioration of image quality. To counter this, a vapor-deposited coating that reduces light reflection is applied to the lens surface. Early coatings consisted of a single thin film with the correct refractive index differences to cancel out reflections. Multi-layer coatings, introduced in the early 1970s, are made up of several such films.

Benefits of anti-reflection coating:

Circular fisheye

Produces a 180° angle of view in all directions (horizontal, vertical and diagonal).

The image circle of the lens is inscribed in the image frame.

Diagonal (full-frame) fisheye

Covers the entire image frame. For this reason diagonal fisheye lenses are often called full-frame fisheyes.

Extension ring

Extension rings can be used singly or in combination to vary the reproduction ratio of lenses. They are mounted between the camera body and the lens. As a rule, the effect becomes stronger the shorter the focal length of the lens in use, and the longer the focal length of the extension ring.

View camera

A large-format camera with a ground-glass viewfinder at the image plane for viewing and focusing. The photographer must stick his head under a cloth hood in order to see the image projected on the ground glass. Because of their 4x5-inch (or larger) negatives, these cameras can produce extremely high-quality results. View cameras also usually support movements.

135 cartridge-loaded film

43.27 24 36
  • Introduced: 1934
  • Frame size: 36 × 24mm
  • Aspect ratio: 3:2
  • Diagonal: 43.27mm
  • Area: 864mm2
  • Double perforated
  • 8 perforations per frame

120 roll film

71.22 44 56
  • Introduced: 1901
  • Frame size: 56 × 44mm
  • Aspect ratio: 11:14
  • Diagonal: 71.22mm
  • Area: 2464mm2
  • Unperforated

120 roll film

79.2 56 56
  • Introduced: 1901
  • Frame size: 56 × 56mm
  • Aspect ratio: 1:1
  • Diagonal: 79.2mm
  • Area: 3136mm2
  • Unperforated

120 roll film

89.64 56 70
  • Introduced: 1901
  • Frame size: 70 × 56mm
  • Aspect ratio: 5:4
  • Diagonal: 89.64mm
  • Area: 3920mm2
  • Unperforated

220 roll film

71.22 44 56
  • Introduced: 1965
  • Frame size: 56 × 44mm
  • Aspect ratio: 11:14
  • Diagonal: 71.22mm
  • Area: 2464mm2
  • Unperforated
  • Double the length of 120 roll film

220 roll film

79.2 56 56
  • Introduced: 1965
  • Frame size: 56 × 56mm
  • Aspect ratio: 1:1
  • Diagonal: 79.2mm
  • Area: 3136mm2
  • Unperforated
  • Double the length of 120 roll film

220 roll film

89.64 56 70
  • Introduced: 1965
  • Frame size: 70 × 56mm
  • Aspect ratio: 5:4
  • Diagonal: 89.64mm
  • Area: 3920mm2
  • Unperforated
  • Double the length of 120 roll film

Shutter speed ring with "F" setting

The "F" setting disengages the leaf shutter and is set when using only the focal plane shutter in the camera body.

Catch for disengaging cross-coupling

The shutter and diaphragm settings are cross-coupled so that the diaphragm opens to a corresponding degree when faster shutter speeds are selected. The cross-coupling can be disengaged at the press of a catch.

Cross-coupling button

With the cross-coupling button depressed speed/aperture combinations can be altered without changing the Exposure Value setting.

M & X sync

The shutter is fully synchronized for M- and X-settings so that you can work with flash at all shutter speeds.

In M-sync, the shutter closes the flash-firing circuit slightly before it is fully open to catch the flash at maximum intensity. The M-setting is used for Class M flash bulbs.

In X-sync, the flash takes place when the shutter is fully opened. The X-setting is used for electronic flash.

X sync

The shutter is fully synchronized for X-setting so that you can work with flash at all shutter speeds.

In X-sync, the flash takes place when the shutter is fully opened. The X-setting is used for electronic flash.

Unable to follow the link

You are already on the page dedicated to this lens.

Cannot perform comparison

Cannot compare the lens to itself.

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.

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 can also be different.

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

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.

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. Magnification is expressed as a ratio. 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.

Manual diaphragm

The diaphragm must be stopped down manually by rotating the detent aperture ring.

Preset diaphragm

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 diaphragm

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 diaphragm

The camera automatically closes the diaphragm down during the shutter operation. On completion of the exposure, the diaphragm re-opens to its maximum value.

Fixed diaphragm

The aperture setting is fixed at F/ on this lens, and cannot be adjusted.

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.

Teleconverters

Teleconverters increase the effective focal length of lenses. They also usually maintain the closest focusing distance of lenses, thus increasing the magnification significantly. A lens combined with a teleconverter is normally smaller, lighter and cheaper than a "direct" telephoto lens of the same focal length and speed.

Teleconverters are a convenient way of enhancing telephoto capability, but it comes at a cost − reduced maximum aperture. Also, since teleconverters magnify every detail in the image, they logically also magnify residual aberrations of the lens.

Lens caps

Scratched lens surfaces can spoil the definition and contrast of even the finest lenses. Lens covers are the best and most inexpensive protection available against dust, moisture and abrasion. Safeguard lens elements - both front and rear - whenever the lens is not in use.