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Nikon D4

35mm AF digital SLR camera

Specification

Production details:
Announced:January 2012
System:● Nikon F (1959)
Format:
Maximum format:35mm full frame
Imaging sensor:36 × 23.9mm CMOS sensor
Resolution:4928 × 3280 - 16 MP
Sensor-shift image stabilization:-
Mount and Flange focal distance:Nikon F [46.5mm]
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:1340g
Dimensions:160x156.5x90.5mm

Manufacturer description

TOKYO - Nikon Corporation is pleased to announce the release of the Nikon D4, a Nikon FX-format camera that serves as the new flagship model in Nikon's lineup of digital-SLR cameras. Nikon will be exhibiting the D4 at the 2012 International CES, to be held Tuesday, January 10 through Friday, January 13 in Las Vegas, Nevada. This electronics exhibition is open to the public.

The D4 is equipped with a new Nikon FX-format CMOS image sensor (imaging size of 36.0 x 23.9 mm) and EXPEED 3, the latest image-processing engine specifically optimized for digital-SLR cameras, making it the next-generation flagship Nikon digital-SLR camera with the ultimate in versatility and functionality that offers superior image quality rich in detail along with excellent high-speed performance. It has an effective pixel count of 16.2-million pixels, and offers superior image quality under a broad range of lighting conditions with its image sensor supporting an incredible range of sensitivities from ISO 50 to ISO 204800.

The new 91K-pixel (approximately 91,000 pixels) RGB sensor supports the Advanced Scene Recognition System, which is able to recognize human faces even when images are framed using the optical viewfinder. In addition, the Advanced Scene Recognition System offers significant improvements in AF, AE, i-TTL flash control, and auto white balance (AWB) control accuracy. The 51 focus point AF system has been improved with faster initiation of autofocusing and the ability to detect and focus on subjects with less lighting. In addition, 11 focus points are fully functional when lenses with a maximum aperture of f/8 are used. All of this means more precise autofocusing when super-telephoto NIKKOR lenses are used with teleconverters (2.0x). The Multi-area Mode Full HD D-movie movie recording function is capable of recording full-HD movies at 30 fps, and offers three movie recording formats for selection according to recording conditions or creative intent.

What's more, the D4 records images to memory cards faster with built-in support for high-speed, UDMA 7-compatible CompactFlash memory cards and next-generation, high-speed XQD memory cards. In addition to built-in wired LAN features, the D4 also supports high-speed image transfer via wireless LAN when the new, compact, easy-to-use Wireless Transmitter WT-5 (available separately) is connected to the camera. The D4 is also equipped with a number of new functions that support a more efficient workflow for professional photographers, including one that allows users to add IPTC (International Press Telecommunications Council) information to images.

Development background

In 2007, Nikon released the D3 digital-SLR camera as its flagship model equipped with the new FX-format CMOS image sensor developed by Nikon. With its new image sensor, the D3 established a new level of image quality, speed, and support for high sensitivities. In December of 2008, Nikon released the D3X with an effective pixel count of 24.5-million pixels, which enabled superior imaging performance equal to that possible with medium format cameras. In the following year, the D3S proposed new possibilities in imaging expression with its expanded range of standard sensitivities from ISO 200 to ISO 12800 and a built-in movie recording function. The superior performance of the Nikon D3 was recognized with three of the most prestigious domestic and international awards—Japan's Camera Grand Prix Camera of the Year and Europe's Technical Image Press Association's (TIPA) Best D-SLR Professional and the European Imaging and Sound Association's (EISA) Professional Camera of the Year. The D3X and D3S continued the success of the series introduced with the D3, being recognized by the camera industry for their superior performance with a number of awards of their own as well as extreme popularity with professional and advanced amateur photographers alike. In addition, the superior durability and reliability of the cameras has also been recognized by NASA, which ordered several models as-is, with no special modification, that are currently used aboard the International Space Station (ISS).

Nikon based development of the flagship D4 on the basic performance achieved with the D3 series, which has led the industry in imaging expression since its release. In addition to this high level of basic performance, a number of new functions and features were added in response to the needs and demands of professional and advanced amateur photographers, resulting in this next-generation digital-SLR camera that stretches the boundaries of functionality and performance with superior versatility.

D4 primary features

1. New Nikon FX-format CMOS image sensor Support for an incredibly wide range of sensitivities, from ISO 50 to ISO 204800

The D4 is equipped with a new Nikon FX-format CMOS image sensor (imaging size of 36.0 x 23.9 mm) developed by Nikon. The superior performance of the FX-format CMOS image sensor with its effective pixel count of 16.2-million pixels offers excellent resolution and image quality under an incredible variety of lighting conditions. Despite the increase in pixel count, the D4 reads out data faster than the D3S. The range of standard sensitivities has been expanded to ISO 100 to ISO 12800. What's more, support for ISO 50 and additional expansion up to ISO 204800 is also possible, enabling effective shooting under a variety of lighting conditions without concern for any sacrifice in image quality.

2. New EXPEED 3 image-processing engine with superior, high-speed processing capabilities

The new EXPEED 3 image-processing engine built into the D4 offers better image quality and even faster processing speeds for vivid yet faithful color reproduction, a broader dynamic range, and rich expression of tones. It also effectively suppresses noise with advanced noise-reduction processing for images captured at high sensitivities under dim lighting, all while preserving definition and sharpness. Noise-reduction processing designed especially for movies maintains crisp, clear outlines in movies recorded in low-light situations. EXPEED 3 has high-speed processing capabilities for a variety of task, and it uses power effectively, contributing greatly to the camera's power-saving design.

3. 91K-pixel RGB sensor for the more accurate Advanced Scene Recognition System

The D4 is equipped with the Advanced Scene Recognition System, which supports face recognition* when images are framed using the optical viewfinder. The new 91K-pixel (approximately 91,000 pixels) RGB sensor recognizes human faces for more frequent focus acquisition on human faces when Auto-area AF AF-area mode is used. When a human face is detected in the frame, 3D Color Matrix Metering III bases exposure control on the brightness of that face so that the face is optimally exposed even with backlighting. In addition, the high resolution of the metering sensor with its roughly 91,000 pixels enables extremely precise analysis of the scene for more accurate control over autofocusing, auto exposure, i-TTL flash control, and auto white balance.

4. Faster and more accurate AF with 51 focus points

The 51 focus point AF system built into the D4 utilizes the new Advanced Multi-CAM 3500FX autofocus sensor module for faster, more accurate autofocusing that performs extremely well under dim lighting.

The 15 focus points at the center of the frame are cross-type sensors that detect phase differences both horizontally and vertically. All 51 focus points are fully functional when lenses with a maximum aperture of up to f/5.6 are used, and the cross-type sensors make the most of this capability. Precise focus can be quickly acquired with autofocusing using all AF NIKKOR lenses, even under lighting as dim as −2 EV (ISO 100, 20°C/68°F), the level at which the scene through the viewfinder can just be made out by the human eye. What's more, 11 focus points (five at center with an additional three to each side) are fully functional when lenses with a maximum aperture of f/8 are used. This enables very precise focus acquisition with sports photography and the like when super-telephoto NIKKOR lenses are used with a teleconverter (2.0x) at a combined aperture value of f/8.

In addition, adoption of a new algorithm enables faster autofocus initiation for even more certain and sharper capture of defining moments especially necessary when shooting sports scenes. The new high-speed AF system also supports high-speed continuous shooting at approximately 10 fps* in FX format with AF and AE tracking.

5. Multi-area Mode Full HD D-movie with three image area options

A dedicated movie-record button has been positioned near the shutter-release button for smooth starting and stopping of movie recording with a feel similar to that of still-image shooting. Full-HD movie recording at a frame size of 1920 x 1080 and frame rate of 30 fps is supported, and the H.264/MPEG-4 AVC video compression method has been adopted. Movies up to 29 minutes 59 seconds*1 can be recorded. Image sensor sensitivity begins at ISO 200 and can be expanded to the same ISO 204800 equivalent possible with still-image shooting.

Full-HD movies can be recorded with the D4 using one of three image areas: FX-based movie format*2, DX-based movie format, or 1920 x 1080; 30 fps/25 fps/24 fps crop. FX-based movie format makes full use of the large image sensor, enabling movies with an emphasis on pleasing blur characteristics. When a DX lens is attached, DX-based format is automatically selected. This format is useful for creating an extension to the local length of an existing lens. For an even stronger telephoto effect, the 1920 x 1080 crop format brings an approximately 2.7x crop of the picture angle while delivering outstanding video quality and detail, obtaining 1080p Full HD. By choosing the movie format appropriate for the particular scene, the three image area options available with a single camera enable more flexible imaging expression through collaboration with the entire NIKKOR lens lineup, including DX lenses.

The D4 is equipped with a connector for external microphones that enables stereo recording. The camera also offers a headphone connector that supports stereo headphones, convenient for checking sound recorded with movies.

6. Smooth workflow from initial setup to image transfer

The entire photographic workflow is faster with the D4. Superior, high-speed response with a power-up time of approximately 0.12 s*1 and a release time lag of roughly 0.042 s*1. In addition, support for high-speed, next-generation XQD memory cards enables a continuous shooting frame rate of 10 fps for up to approximately 100 shots even with shooting in RAW format*2. The camera is also equipped with dual memory card slots, one for XQD memory cards and one for CompactFlash memory cards, for smooth handling of images. What's more, professional photographers can work much faster with high-speed transfer of images to a computer when an XQD memory card reader supporting SuperSpeed USB (USB 3.0)*3 is used.

7. The new compact Wireless Transmitter WT-5 with simple connection to the camera (available separately)

The D4 is equipped with an Ethernet port and functions for wired LAN connections. In addition, it also supports the new WT-5 (available separately), a compact wireless transmitter that is easily connected to the camera for high-speed transfer of images over a wireless network.* The D4 is also equipped with a number of new functions that support a more efficient workflow for professional photographers, including one that allows users to add IPTC (International Press Telecommunications Council) information to images. The new WT-5 is powered by the camera, making a more compact size possible. In addition to IEEE 802.11a/b/g standards, the WT-5 also supports the new IEEE 802.11n (1 x 1) standard, enabling data transfer at twice the speed possible with the WT-4. The camera's HTTP server mode can be used to display a list of images stored on the memory card, and also enables basic camera control, live view, movie recording, etc. using the Web browser on a computer or smartphone. Synchronized release (WT-5 only) mode enables synchronized shutter release of up to 10 D4 cameras, each with its own WT-5) with the D4 used as the controlling "master".

Other D4 functions and features

  • Extremely durable shutter that has passed testing for 400,000 cycles
  • Magnesium alloy adopted for the very strong, durably body that is very resistant to dust and water
  • Effective sealing using O rings and packing make the camera more resistant to dust and water
  • Silent shutter-release mode for live view photography that almost completely eliminates the sounds of the mirror and shutter operation
  • A time-lapse photography feature, with which the camera automatically takes photos at selected intervals to record a time-lapse movie, which can be played back at 24–36,000x normal playback speed
  • Operation optimized for both horizontal (landscape) and vertical (portrait) shooting
  • Button backlights (illuminators) for increased visibility when working in dimly lit or dark situations
  • High-performance viewfinder, utilizing a glass pentaprism, with a frame coverage of approximately 100% (FX format) and magnification of approximately 0.7x
  • Four image area options for still shooting—FX (36 x 24), 5:4 (30 x 24), 1.2x (30 x 20), DX (24 x 16)—with viewfinder indicator that identifies the current image area
  • A 3.2-inch, approximately 921k-dot LCD monitor with reinforced glass and wide viewing angle; integration of the glass and panel reduce internal reflections
  • A virtual horizon that shows the degree to which the camera is tilted sideways (roll), forward or backward (pitch) with display in the monitor and viewfinder
  • White balance that can be adjusted in units of 10 K; white balance can be specified separately for shooting (white balance applied to images) and monitor display with still-image shooting in live view mode

8. Capture NX 2 Ver. 2.3 for significantly faster processing

A trial version and free upgrade for Capture NX 2, Nikon's image editing software, were released on December 20 to coincide with release of the D4. This latest version is Capture NX 2 Ver. 2.3. In addition to offering image editing functions that allow users to achieve the intended results with intuitive operation, a faster image-processing algorithm has been adopted for much faster processing. What's more, operation is smoother and more natural with the addition of native compatibility with 64-bit operating systems.

Similar cameras (2)

35mm full frame • Auto focus • Digital • Singe-lens reflex • Nikon F mount

Model Shutter Metering Modes Year
Kodak DCS Pro 14n E, 1/4000 TTL • OA PASM 2002
Kodak DCS Pro SLR/n E, 1/4000 TTL • OA PASM 2004
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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.