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Pentax K-1 Mark II

35mm AF digital SLR camera

Specification

Production details:
Announced:February 2018
System:● Pentax K (1975)
Format:
Maximum format:35mm full frame
Imaging sensor:35.9 × 24mm CMOS sensor
Resolution:7360 × 4912 - 36 MP
Sensor-shift image stabilization:Yes
Mount and Flange focal distance:Pentax K [45.5mm]
Shutter:
Type:Focal-plane
Model:Electronically controlled
Speeds:30 - 1/8000 + B
Exposure:
Exposure metering:Through-the-lens (TTL), open-aperture
Exposure modes:Programmed Auto
Aperture-priority Auto
Shutter-priority Auto
Manual
Physical characteristics:
Weight:925g
Dimensions:136.5x110x85.5mm

Manufacturer description

WEST CALDWELL, NJ, February 21, 2018－Ricoh Imaging Americas Corporation today announced the PENTAX K-1 Mark II 35mm full-frame digital SLR (DSLR) camera. Developed as the successor to the PENTAX K-1 full-frame DSLR camera launched in April 2016, the compact, rugged and weather-resistant PENTAX K-1 Mark II now becomes the flagship camera in the acclaimed PENTAX K-series lineup. The camera incorporates new technologies that allow it to deliver outstanding image quality and improved operability in a broader range of shooting conditions.

The PENTAX K-1 Mark II uses the same full-frame Anti-aliasing (AA)-filterless CMOS sensor with 36.4 effective megapixels as its predecessor model. However, Ricoh has added a new accelerator unit to the PENTAX K-1 Mark II that—along with the camera’s PRIME IV image processor—enables it to produce high-resolution images with minimal noise in even in the most challenging low-light conditions, up to ISO 819200. This makes the new camera ideal for low-light photography where higher shutter speeds are required.

The camera also incorporates Pixel Shift Resolution System II. This new, PENTAX-developed technology uses the same in-camera shake-reduction (SR) mechanism and sensor-shift capabilities as the original Pixel Shift Resolution System found in the PENTAX K-1, which captures four images of the same scene, and then synthesizes them into a single, super-high-resolution composite image. With the Pixel Shift Resolution System II, the camera also obtains RGB color data, resulting in images with significantly finer details and truer colors than those produced by typical full-frame sensors.

A new feature in the Pixel Shift Resolution System II is Dynamic Pixel Shift Resolution mode. This mode allows photographers to produce crisp, ultra-high pixel shift resolution images without the need of a tripod, extending the camera’s use to a wider variety of subjects and scenes.

The PENTAX K-1 Mark II also comes equipped with many unique features and functions designed to facilitate creativity and ensure operational comfort that have become the hallmark of PENTAX cameras. These include a sturdy magnesium-alloy body with dustproof, weather-resistant construction; an optical viewfinder with a nearly 100-percent field of view for real-time subject confirmation; Astro Tracer, which simplifies the tracing and photographing of celestial bodies by coupling GPS data with the camera's sophisticated SRII mechanism; and a flexible tilt-type LCD monitor to accommodate various shooting angles.

| Pricing and Availability |

The PENTAX K-1 Mark II camera body will be available in April 2018 for a suggested list price of $1,999.95. The camera body plus HD PENTAX-D FA 28-105mm F3.5-5.6 ED DC WR zoom lens will also be available for a suggested list price of $2,399.95. Both can be purchased at www.us.ricoh-imaging.com as well as at Ricoh Imaging-authorized retail outlets throughout North America.

| Main Features |

1. Newly incorporated accelerator unit delivers high-quality images and excellent super-high-sensitivity imaging performance

The PENTAX K-1 Mark II features a 35mm-format full-frame CMOS image sensor with an AA (anti-aliasing) filter–free design to produce high-resolution images with approximately 36.4 effective megapixels. It also features a new accelerator unit, which optimizes the image data obtained by the full-frame image sensor before delivering it to the high-performance PRIME IV imaging engine. As a result, the camera is capable of producing high-quality images with minimal noise, while retaining excellent resolution at all sensitivity levels, from normal to super-high sensitivities. PENTAX has also updated all image-processing parameters to ensure colors are true to life, with special emphasis on deep blues and lively greens. PENTAX has also dramatically improved the camera’s noise-reduction performance at a high-sensitivity range — up to ISO 819200 — to expand creative possibilities in super low-light shooting.

2. Pixel Shift Resolution System II produces super-resolution images and enables handheld shooting

Building upon the original PENTAX-developed Pixel Shift Resolution System — the super-resolution technology that uses the camera’s in-body shake-reduction mechanism to capture four images of the same scene by shifting the image sensor by a single pixel for each image, and then synthesizes them into a single composite image — is the Pixel Shift Resolution System II,* making its debut in the PENTAX K-1 II. This new system obtains RGB color data for each pixel, resulting in super-high-resolution images with finer details and more realistic colors than those produced by cameras with ordinary full-frame sensors. The Motion Correction functions provides ON/OFF switching, which detects moving elements of the continuously captured images to minimize the effect of subject movement during the image synthesizing process.***The new Dynamic Pixel Shift Resolution mode,** which can be used during handheld shooting, works together with the camera’s shake-reduction mechanism, by synthesizing the composite images while detecting the slight fluctuations of the subject’s position during the capture process.

This technology comes from the reverse thinking of pixel shift technology to utilize the minute camera shake itself to product the composite images. Therefore, by detecting the camera shake in three dimensions, the continuously captured four images are analyzed based on the detected camera shake information and combined into a single file to produce one super high resolution image.

3. High-performance five-axis, five-step SR II system

(1) In-body SR mechanism delivers optimal shake-reduction performance with all compatible lenses The PENTAX K-1 Mark II comes equipped with the PENTAX-developed SR II (Shake Reduction II) five-axis mechanism, which provides accurate control of the large full-frame image sensor with all compatible PENTAX interchangeable lenses.* In addition to camera shake caused by pitch and yaw, this advanced system also compensates for camera shake caused by horizontal and vertical shift (often generated in macro photography) and camera shake caused by roll, which is difficult for lens-installed shake-reduction mechanisms to handle. It has a compensation range up to five steps (measured in conformity with CIPA standards, using the HD PENTAX-D FA 28-105mm F3.5-5, 6ED DC WR at a 105mm focal length). When taking a panning shot, this system automatically detects the direction of the camera’s movement, and efficiently controls the SR unit to produce the best image possible without requiring any mode switching operation.

(2) Innovative AA filter simulator to minimize moiré and inaccurate color rendition By applying microscopic vibrations to the image sensor unit at the sub-pixel level during image exposure, the camera’s anti-aliasing (AA) filter simulator** provides the same level of moiré reduction as an optical AA filter. Unlike an optical filter, which always creates the identical result, this innovative simulator not only lets the user switch the AA filter effect on and off, but also adjust the level of the effect. This means that the ideal effect can be set for a particular scene or subject based on given photographic conditions.

(3) Additional shooting functions enabled by the SR II system Since the camera’s SR unit has a flexible design that tilts the image sensor unit in all directions, additional shooting functions are enabled, including auto level compensation, image-composition fine-adjustment, and Astro Tracer, a feature that works along with the built-in GPS, to produce super-sharp images of the night sky.

4. Flexible, tilting LCD monitor facilitates shooting in the dark On its back panel, the PENTAX K-1 Mark II features a flexible, tilting LCD monitor, which can be adjusted to the desired angle horizontally, vertically or diagonally with a single adjustment, without deviating from the lens’s optical axis. The user can not only tilt it approximately 35 degrees horizontally and approximately 44 degrees vertically, but also pull it out from its base to view the on-screen image from above for waist-level photography. This large, 3.2-inch LCD monitor has approximately 1,037,000 dots and a 3:2 aspect ratio, and provides a protective tempered-glass front panel for added durability. In addition to its wide-view design, it also features a unique air-gapless construction, in which the air space between LCD layers is eliminated to effectively reduce the reflection and dispersion of light for improved visibility during outdoor shooting. Its outdoor monitor function, which allows instant adjustment of the monitor’s brightness to the desired level, has also been improved to provide greater visibility in dark locations. Its red-lit monitor display function facilitates monitor viewing when the photographer’s eyes have become accustomed to a dark location during nighttime photography.

5. SAFOX 12 with 33 sensor points and full-frame-proportioned AF frame Using a SAFOX 12 AF sensor module with 33 AF sensors (25 cross-type sensors positioned in the middle), the PENTAX K-1 Mark II optimizes the autofocus process, and assures high-speed autofocus operation in the AF.S (AF Single) mode. The center sensor and two sensors located just above and below it are designed to detect the light flux of an F2.8 lens, making it easy to obtain pinpoint focus on a subject when using a large-aperture lens. Its AF Tracking algorithm has also been revised to improve tracking accuracy of fast-moving subjects in the AF.C (AF Continuous) mode.

6. PENTAX Real-Time Scene-Analysis System, developed using artificial intelligence technology By combining an approximately 86,000-pixel RGB metering sensor with the high-performance PRIME IV imaging engine, the PENTAX K-1 Mark II’s advanced PENTAX Real-Time Scene Analysis System performs real-time analysis of the brightness distribution over the image field and the subject’s colors and movement. Based on this data, it then measures the subject’s lighting conditions with great accuracy and optimizes the exposure. By adopting a breakthrough artificial intelligence technology, deep learning, to its algorithm,* it assesses each individual scene more accurately, and optimizes the exposure settings for a given scene or composition.

7. Easy-to-focus optical viewfinder with nearly 100-percent field of view Optimized for a 35mm full-frame digital SLR design, the camera’s optical viewfinder provides a nearly 100-percent field of view and an approximately 0.7-times magnification. Using a combination of a condenser lens and aspherical lens, it provides a wide field of view and a clear, undistorted image of the subject. It comes with a Natural Bright Matt III focusing screen, acclaimed for ease of focusing during manual-focus operation, and true-to-life rendition of defocused areas in the viewfinder image. In addition, its transparent viewfinder display makes it possible to superimpose a wide range of photographic data over the viewfinder image.

8. High-speed continuous shooting The PENTAX K-1 Mark II allows continuous recording of as many as 17 images in the RAW format (or a maximum of 70 images in the JPEG Best format) in a single sequence, at a top speed of approximately 4.4 images per second. This is made possible by the combination of advanced mechanisms including a damper mechanism that effectively minimizes mirror shock; high-speed, high-precision control of the shutter and mirror units; and a high-speed data transmission system incorporated in the PRIME IV imaging engine. In the APS-C Crop mode, the drive speed can be boosted to as high as approximately 6.4 images per second, and as many as 50 images in a single sequence in the RAW format (or 100 images in the JPEG Best format) to assure quick response to fast-moving subjects.

9. Supportive shooting functions to improve picture-taking efficiency and operational comfort

  • Operation-assist light function, which sets LED lights at four different spots around the camera body — above the lens mount, behind the LCD monitor, at the memory car slot, and at the cable switch terminal — to facilitate lens and memory card changes, attachment and removal of the cable switch, and control button operation at night and in poorly lit settings.
  • Key lock function, which prevents erroneous operation of the four-way controller and other exposure-related control buttons.
  • Smart Function, which allows the user to swiftly choose and set desired functions using just the function dial and the set dial on the camera’s upper panel, without referring to the menu screen on the LCD monitor.
  • Control panel customize function, which allows the user to change a listing and/or position of the on-screen menu.

10. Compact, rugged body with dustproof, weather-resistant construction The camera’s bottom panel and front and back frames are all made of sturdy yet lightweight magnesium alloy. Although the camera features a dependable, durable shutter unit that can withstand 300,000 shutter releases (measured under actual shooting conditions) for professional use, its body has been downsized to the minimum possible, thanks to the incorporation of a unique floating mirror structure. With the inclusion of 87 sealing parts in the body, the camera also boasts a dustproof, weather-resistant and cold-resistant construction, assuring solid operation at temperatures as low as -10°C. All these features make the PENTAX K-1 Mark II a dependable, all-purpose performer, even under demanding shooting conditions.

11. Full HD movie recording with an array of creative tools The PENTAX K-1 Mark II captures Full HD movie clips (1920 x 1080 pixels; 60i/30p frame rate) in the H.264 recording format, and comes equipped with a stereo mic terminal for external microphone connection, and a headphone terminal. The user can also adjust the audio recording level manually, monitor sound pressure levels during microphone recording, and cut down wind noise using a new wind-noise reduction mode. In addition to a host of distinctive visual effects for movie recording,* the camera also provides the interval movie mode, which captures a series of 4K-resolution (3840 x 2160 pixels) movie clips at a fixed interval.

12. Built-in GPS module The PENTAX K-1 Mark II provides a variety of advanced GPS functions, including the recording of location, latitude, longitude, altitude and UTC (Universal Time Coordinated) and direction at the time of shooting. The user can easily access images containing GPS data using a computer, to browse them, check on shooting locations and position data on the screen, or save them. The camera also provides a set of other unique tools, including: Electronic Compass, which displays the camera's direction on its LCD monitor; GPS log, which keeps track of the photographer's movement; and Astro Tracer, which simplifies the tracing and photographing of celestial bodies by coupling GPS data with the camera's SR mechanism.

13. Other features

  • High-grade DRII (Dust Removal II) mechanism for effective elimination of dust on the image sensor using ultrasonic vibration
  • Crop mode with a choice of image area from AUTO, FF (Full Frame), APS-C and 1:1
  • Wireless LAN connection to support the operation with smartphones and table computers, the transfer of captured images, and remote shooting operations ・HDR (High Dynamic Range) shooting mode with RAW-format data filing, usable in handheld shooting
  • The PENTAX-invented hyper operating system for quick, accurate response to the photographer's creative intentions
  • Dual SD card slots for memory card flexibility (compatible with SDXC UHS-1 speed class in SDR104 bus speed mode)
  • Compensation of various parameters: lens distortion, lateral chromatic aberration, diffraction, and brightness level at image-field edges. Fringe effect compensation is also available in RAW-format processing.
  • Bulb Timer function to improve operability in bulb shooting
  • Compatibility with PENTAX Image Transmitter 2 tethering software (software update required from RICOH IMAGING official website)
  • Digital Camera Utility 5 software (latest version) included

Special limited editions (2)

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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.