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Pentax K-70

APS-C AF digital SLR camera

Specification

Production details:
Announced:June 2016
System:● Pentax K APS-C (2003)
Format:
Maximum format:APS-C
Imaging sensor:23.5 × 15.6mm CMOS sensor
Resolution:6000 × 4000 - 24 MP
Crop factor:1.53x
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:628g
Dimensions:125.5x93x74mm

Manufacturer description

DENVER, Colo., June 8, 2016—Ricoh Imaging Americas Corporation today announced the PENTAX K-70 advanced digital single-lens reflex (SLR) camera. Compact, dustproof and weather-resistant, the new PENTAX K-70 camera incorporates features — many of which have previously only been available on top-of-the-line PENTAX models — that enable photographers to produce high-resolution still photos and HD videos in a wide variety of challenging conditions, including low light and temperatures as low as 14°F (-10°C). The camera’s weather-resistant capabilities and compact design make it an ideal photographic companion for hikers, climbers and snow sports enthusiasts, as well as for nature and landscape photographers.

With a newly developed image accelerator unit providing a top sensitivity of ISO 102,400, plus the PENTAX-developed PRIME MII image processor, the PENTAX K-70 is capable of capturing high quality images in extremely low-light conditions. A new Hybrid Autofocus (AF) system, integrating both image-plane phase-matching and contrast-detection autofocus technologies, delivers speedy and accurate autofocus while also providing continuous auto focus for HD video recording.

“PENTAX has a long history of developing cameras and lenses that can withstand the rigors of the great outdoors. The K-70 goes a step further, with new, advanced features that enable the creation of higher quality images and make the camera very easy to use, both in the backyard and in the field,” said Kaz Eguchi, president, Ricoh Imaging Americas Corporation. “Combined with any one of our many available weather-resistant lenses, this camera is in a class of its own for outdoor photography.”

The PENTAX K-70 provides a variety of advanced features found only in Ricoh’s high-grade PENTAX K-series models, such as the PENTAX Pixel Shift Resolution System, which produces high-resolution, finely detailed images. These also include an AA Filter Simulator that effectively eliminates moiré without the need for an anti-aliasing filter, a variable-tilt LCD monitor, and an in-body shake-reduction mechanism that reduces the effects of camera shake up to 4.5 shutter steps. The K-70 also incorporates built-in Wi-Fi for remote shooting and easy transfer to smart devices using Ricoh’s dedicated Image Sync app.

The PENTAX K-70’s exterior is designed with outdoor operations in mind. Features such as a newly designed grip, mode dial and control buttons on the camera’s top and back panels are designed to be easy and intuitive to operate, even with a gloved hand. It also comes equipped with an outdoor-friendly LCD monitor with an illumination control that can be instantly adjusted to the lighting level of any shooting location. The K-70 also has a red-lighted monitor display function which keeps ambient light from interfering with astrophotography.

In conjunction with the PENTAX K-70 camera, Ricoh Imaging is announcing the HD PENTAX-DA 55-300mm f/4.5-6.3ED PLM WR RE lens, a compact, weather-resistant telephoto zoom (see details in separate news release, also issued today); plus the Cable Switch CS-310, a remote shutter release designed especially for use with the K-70.

| Pricing and Availability |

Availability of the PENTAX K-70 camera, which comes in black and silky silver finishes, will be announced at the beginning of July. When available, it can be purchased at www.ricohimaging.com for $649.95, as well as at Ricoh Imaging-authorized retail outlets throughout North America.

Main Features

1. Super-high-resolution images captured with approximately 24.24 effective megapixels and at ISO 102400

The PENTAX K-70 features a state-of-the-art CMOS image sensor with approximately 24.24 effective megapixels to assure high-speed 14-bit image data readout. Combined with an AA-filter-free optical design, this image sensor delivers super-high-resolution images. Also, by coupling a newly developed accelerator unit with the high-speed PRIME MII imaging engine, the PENTAX K-70 effectively minimizes noise at all sensitivity levels, and captures rich-gradation, fine-detailed images even in super-high-sensitivity shooting at a top sensitivity of ISO 102400.

2. Hybrid AF system for high-speed AF operation during Live View shooting

The PENTAX K-70 employs PENTAX's first Hybrid AF system during Live View autofocus operation. By positioning a contrast-detection AF sensor with superior focusing accuracy and a phase-matching AF sensor on the image sensor's surface, this innovative hybrid system optimizes the benefits of both AF systems to assure high-speed, pinpoint AF focusing on the subject.

3. Dustproof, weather-resistant body perfect for rugged outdoor photography

The PENTAX K-70 is a dependable performer even in such demanding settings as in the rain or at locations prone to dust and freezing temperatures, because it combines a compact, easy-to-carry body with a dustproof, weather-resistant construction and outstanding cold-proof performance at temperatures down to -10°C. It has also been designed for active outdoor shooting -- such as mountain climbing, camping and sporting events. This was accomplished by improving its operability, with a new grip design that provides firm hold of the camera body even with a gloved hand, and through a complete design review of the mode dial and control buttons. In addition to its outdoor-friendly LCD monitor, whose brightness level can be instantly adjusted to the lighting level of a shooting location, it also features a red-lighted monitor display function, which works friendly to the photographer's eye when it has become accustomed to a dark location during astronomical photography.

4. High-precision autofocus system with the SAFOX X module

The PENTAX K-70 features the high-precision SAFOX X AF sensor module, which assures responsive, dependable autofocus operation. With its 11 sensors including nine cross-type sensors in the middle, this AF module assures pinpoint focus on the subject at a minimum brightness level as low as -3 EV. By revising the timing of the AF sensor's start-up action, the speed of autofocus response has been improved, especially at low-illumination levels. Also, by improving the algorithm for moving objects, the focusing accuracy in the AF-C mode has been enhanced. The PENTAX K-70 even assures outstanding AF tracking performance with subjects on the move, thanks to such advanced features as the Select-area Expansion function, which automatically refocuses on a moving subject after it moves away from the initial point, with the help of the neighboring points; and an AF Hold function that maintains the initial in-focus point even when the module loses sight of the subject.

5. PENTAX-original shake-reduction system featuring the Pixel Shift Resolution System

(1) In-body SR mechanism

Thanks to the built-in PENTAX-original SR (Shake Reduction) mechanism, the PENTAX K-70 effectively minimizes camera shake and delivers sharp, blur-free images, even in camera-shake-prone conditions such as when using a telephoto lens, shooting low-light scenes with incident light only, or photographing sunset scenes. Using a high-accuracy gyro sensor, it provides a compensation effect of 4.5 shutter steps, a level close to that of upper-class models. When taking a panning shot, this mechanism 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) Pixel Shift Resolution System with motion correction function

The PENTAX K-70 features the latest super-resolution technology called Pixel Shift Resolution System,* which captures four images of the same scene by shifting the image sensor by a single pixel for each image, then synthesizes them into a single composite image. Compared to the conventional Bayer system, in which each pixel has only a single color data unit, this innovative system obtains all color data in each pixel to deliver super-high-resolution images with far more truthful colors and much finer details than those produced by conventional APS-C-size image sensors. This system even provides a motion correction function,** which automatically detects a moving object during continuous shooting and minimizes negative effects during the synthesizing process, in order to accommodate a wider range of scenes and subjects.

(3) Innovative AA filter simulator to minimize moiré

By applying microscopic vibrations to the image sensor unit at the sub-pixel level during image exposure, the PENTAX K-70's AA (anti-aliasing) filter simulator*** provides the same level of moiré reduction as an optical AA filter. Unlike an optical AA filter, which always creates the identical result, this innovative simulator lets the user switch the AA filter effect on and off, and adjust the level of the effect. This means that the ideal effect can be set for a particular scene or subject based on the current photographic conditions.

(4) Supportive shooting functions

Since the PENTAX K-70's SR unit has a flexible design that tilts the image sensor unit in all directions, it provides a host of handy shooting functions, including ASTRO TRACER, which simplifies advanced astronomical photography in combination with an optional O-GPS1 GPS Unit.* When using this system, the user is advised to stabilize the camera firmly on a tripod. When a moving subject is captured in the camera's image field, its image may not be reproduced clearly, either in part or as a whole.** The movement may not be sufficiently corrected when the object is moving in a certain direction and/or pattern. This function does not guarantee that the movement is properly corrected with all subjects.*** This function works most effectively with a shutter speed of 1/1000 second or slower. This function may not be combined with some shooting modes, including the Pixel Shift Resolution system.

6. Optical viewfinder with nearly 100-percent field of view

Within its compact body, the PENTAX K-70 incorporates a glass prism finder featuring the same optics and coatings as those used in higher-level models. With a nearly 100-percent field of view and a magnification of approximately 0.95 times, it provides a wide, bright image field for easy focusing and framing.

7. High-speed shutter to capture fast-moving subjects in crisp focus

With a top shutter speed of 1/6000 second, the PENTAX K-70 captures sharply focused images, even with fast-moving subjects. Coupled with its high-speed continuous shooting function with a top speed of approximately six images per second, it lets the photographer preserve once-in-a-lifetime shutter opportunities in beautifully focused images.

8. Upgraded Full HD movie recording

The PENTAX K-70 captures high-resolution, flawless Full HD movie clips (1920 x 1080 pixels; 60i/30p frame rate) in the H.264 recording format, and records lively stereo sound using a built-in stereo microphone. In combination with compatible lenses, it allows the user to use the Continuous AF (AF-C) mode* to keep accurate focus on a moving subject, or take advantage of a new aperture control function** to automatically assure a proper exposure level even in fluctuating lighting conditions during movie recording. It also provides a host of distinctive visual effects for movie production, including the 4K Interval Movie mode that connects a series of 4K-resolution still images at a fixed interval to create a single movie file, and a Star Stream mode to fade in and out the traces of stars to recorded movies.* During movie recording, the Continuous AF (AF-C) mode can be used in combination with the HD PENTAX-DA 55-300mm F4.5-6.3ED PLM WR RE or smc PENTAX-DA 18-135mm F3.5-5.6ED AL[IF] DC WR lens. Access the RICOH IMAING official website for details.** During movie recording, the aperture control function is available only in combination with the HD PENTAX-DA 55-300mm F4.5-6.3ED PLM WR RE lens.

9. Vari-angle LCD monitor for easy image viewing from all angles

Since the PENTAX K-70's vari-angle LCD monitor allows for the positioning of the monitor at any desired angle, it makes it easier to compose the image in a wide variety of applications, such as high-angle shooting using stretched arms or low-angle shots taken from ground level. 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.

10. An array of functional customization options

The PENTAX K-70 allows a choice of menu items and the order of their listing displayed on the control panel, so that the user can confirm or change the listed functions and their current settings at a glance. The user can also assign one of the seven functions to each of two Fx (Function) buttons. The PENTAX K-70 also provides three USER modes, to which the user can assign desired camera settings depending on subject types or creative intentions. Three settings (CLEAR TONE, HDR LANDSCAPE and ASTROPHOTO) are preprogrammed in the camera as default.

11. Wireless LAN connection to support smartphone operation

The PENTAX K-70 provides a host of wireless LAN (Wi-Fi) functions to support operations using smartphones and tablet computers. By installing the dedicated Image Sync application in a mobile device, the user can remotely check the Live View image, capture still images, and adjust such camera settings as aperture, shutter speed and ISO sensitivity to the desired level through the mobile device. It is even possible to download captured images onto the mobile device, then upload them on social networking service websites.

12. Other features

  • 77-segment multi-pattern metering system for high-precision light metering
  • DR (Dust Removal) mechanism to shake dust off from the surface of the CMOS image sensor
  • Timer exposure mode-- a new shooting feature incorporated for the first time in a PENTAX digital SLR camera -- which allows the user to expend an exposure time to as long as 20 minutes in Bulb mode, and automatically closes the shutter when the user-selected exposure time expires
  • A pair of e-dials for efficient control of the PENTAX-invented hyper operating system
  • Self-timer function, which even works in the Continuous AF (AF-C) mode
  • Clarity control and Skin Tone correction functions -- a pair of the latest image processing technologies developed by RICOH Central Laboratory
  • A selection of imaging tools, such as Custom Images, Digital Filters and Scene Modes

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.