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Nikon Nikkor-O 21mm F/4

Ultra-wide angle prime lens • Film era • Discontinued

Model history

Nikon AI-S Nikkor 20mm F/3.5A11 - 80.3m⌀52 1981 
Nikon AI Nikkor 20mm F/3.5A11 - 80.3m⌀52 1977 
Nikon AI Nikkor 20mm F/4A10 - 80.3m⌀52 1977 
Nikon Nikkor 20mm F/4A10 - 80.3m⌀52 1974 
Nikon Nikkor-UD Auto 20mm F/3.5A11 - 90.3m⌀72 1967 
Nikon Nikkor-O 21mm F/4Pancake lensNon-retrofocusM8 - 40.9m⌀52 1959 

Features highlight

Extreme AoV
Non-retrofocus
Manual
MF
Compact
Lightweight

Specification

Production details
Announced:October 1959
Production status: Discontinued
Production type:Mass production
Original name:Nippon Kogaku NIKKOR-O 1:4 f=2.1cm
System: Nikon F (1959)
Optical design
Focal length:21mm
Speed:F/4
Maximum format:35mm full frame
Mount and Flange focal distance:Nikon F [46.5mm]
Diagonal angle of view:91.7° (35mm full frame)
67.9° (Nikon F APS-C)
Lens construction:8 elements - 4 groups
Non-retrofocus
Diaphragm mechanism
Diaphragm type:Manual
Number of blades:7
Focusing
Closest focusing distance:0.9m
Maximum magnification ratio:<No information>
Focusing method:<No information>
Focusing modes:Manual focus only
Manual focus control:Focusing ring
Physical characteristics
Weight:210g
Maximum diameter x Length:⌀60×16.5mm
Weather sealing:-
Fluorine coating:-
Accessories
Filters:Screw-type 52mm
Lens hood:Screw-type HN-14 (round)
Teleconverters:<No information>

*) Sources of data: Manufacturer's technical data ● Nikon for flexibility & versatility booklet ● Nikon cameras, Nikkor lenses, Nikon accessories booklet ● The Nikon system of photography booklet (September 1965).

Compatibility

  • This non-AI lens was designed for Nikon F, F2, Nikkormat FS, FT, FT2, FTN, EL, ELW 35mm film SLR cameras.
  • Non-AI lenses cannot be used on Nikon digital SLR cameras (except for the Df) or late (AI) film SLR cameras. However, non-AI lenses can be fitted to Nikon FM, FE, EL2, F3, F4 and Nikkormat FT3 cameras which used the AI metering system but allowed the metering coupling lever to be disengaged. The F5 could have this mechanism fitted as an optional extra. Non-AI lenses can be also fitted to the Nikon F2A and F2AS cameras because the AI mechanism was fitted to the removable metering prism.

Manufacturer description #1

Nowhere is the quality of Nikkor optics better demonstrated than in the critical demands of this extra-wideangle lens. Despite its 92 deg. angle of view, it offers unusual resolution, true color rendition and almost no linear distortion. Click-stops to f 16. Focuses down to 3 feet or 90 cm. Accepts 52 mm screw-in filters. Non-meter coupling. Supplied with these components: leather case and supplementary viewfinder. Deep-seat-mount requires mirror to be locked in "up" position.

Manufacturer description #2

Supplied with front and rear caps. Fits Nikon F (with mirror locked up).

Nowhere is the quality of Nikkor optics better demonstrated than in the critical demands of this new extra-wide angle lens. Despite its 92° angle of coverage, it offers unusual resolution, high color correction, and no linear distortion. Features 8-elements. Click-stops to f22. Focuses to 3'. Accepts 52mm screw-in filters.

Manufacturer description #3

Despite the extra wide angle, this lens assures high definition all over the picture field without vignetting; astigmatism is especially well-corrected and distortion is reduced to within 1%. Hence, it is especially suited for photographing an extended landscape, architectural interior, etc. or for intentionally exaggerated perspective. It gives such a great depth of field that even at full aperture all the subjects from infinity to 2 meters (about 6 ft) are included within the range of sharpness when the lens is focused to 4 meters (about 12 ft). Owing to its symmetrical design, the high definition of the lens is maintained for close distance photography. With the Bellows Focusing Attachment, this lens can produce an image larger than natural size.

Mirror in the camera must be kept in flip-up position because of the deep-seated mount of the lens, and the Supplementary Viewfinder should be used on the camera shoe.

There are two discontinued types of Supplementary Viewfinders. One has a bakelite base and the other requires the Flash Unit Coupler to attach the finder to the camera.

Typical application

landscapes, interiors, buildings, cityscapes, travel

Notes and recommendations

Lenses with similar focal length

Sorted by manufacturer name

3.5 Carl Zeiss Classic Distagon T* 18mm F/3.5 ZE / ZF / ZF.2 / ZK E82Pro 2008 
2.8 Carl Zeiss Classic Distagon T* 21mm F/2.8 ZE / ZF / ZF.2 / ZK E82Pro 2008 
3.5 Cosina Voigtlander Color-Skopar 20mm F/3.5 Aspherical SL II ⌀52Pro 2009 
3.5 Cosina Voigtlander Color-Skopar 20mm F/3.5 Aspherical SL II N ⌀52Pro 2012 
1.4 Irix 21mm F/1.4Pro 2022 
2.0 Kino Precision Kiron 24mm F/2 MC ⌀55
4.0 Nikon AI Nikkor 18mm F/4 ⌀86Pro 1977 
3.5 Nikon AI Nikkor 20mm F/3.5 ⌀52Pro 1977 
4.0 Nikon AI Nikkor 20mm F/4 ⌀52Pro 1977 
2.0 Nikon AI Nikkor 24mm F/2 ⌀52 1977 
2.8 Nikon AI Nikkor 24mm F/2.8 ⌀52 1977 
3.5 Nikon AI-S Nikkor 18mm F/3.5 ⌀72Pro 1981 
2.8 Nikon AI-S Nikkor 20mm F/2.8 ⌀62Pro 1984 
3.5 Nikon AI-S Nikkor 20mm F/3.5 ⌀52Pro 1981 
2.0 Nikon AI-S Nikkor 24mm F/2 ⌀52 1981 
2.8 Nikon AI-S Nikkor 24mm F/2.8 ⌀52 1981 
4.0 Nikon Nikkor 18mm F/4 ⌀86Pro 1974 
4.0 Nikon Nikkor 20mm F/4 ⌀52Pro 1974 
2.8 Nikon Nikkor 24mm F/2.8 ⌀52 1975 
2.8 Nikon Nikkor-N[·C] Auto 24mm F/2.8 ⌀52 1967 
3.5 Nikon Nikkor-UD Auto 20mm F/3.5 ⌀72Pro 1967 
1.8 Samyang 20mm F/1.8 ED AS UMC (Bower, Rokinon, Walimex Pro) ⌀77Pro 2016 
1.4 Samyang 24mm F/1.4 ED AS UMC (Bower, Rokinon, Walimex Pro) ⌀77 2012 
2.8 Sigma MF 18mm F/2.8 ⌀67Pro 1980 
2.8 Sigma MF 18mm F/2.8 II ⌀72Pro 1985 
3.5 Sigma MF 18mm F/3.5 ZEN ⌀72Pro 1992 
2.8 Sigma MF 24mm F/2.8 ⌀52 1981 
2.8 Sigma MF 24mm F/2.8 II ⌀52 1986 
2.8 ZEISS Milvus Distagon T* 18mm F/2.8 ZE / ZF.2 E77Pro 2016 
2.8 ZEISS Milvus Distagon T* 21mm F/2.8 ZE / ZF.2 E82Pro 2015 

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35mm full frame

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

Pancake lens

Pancake lenses get their name due to the thin and flat size. The other distinctive features are fixed focal length and light weight.

First pancake lenses appeared in the 1950s and were standard prime lenses based on the famous Tessar design – a brilliantly simple design which was developed by Paul Rudolph in 1902, patented by Zeiss company and provided a good optical performance.

With the improvement of optical technologies in the 1970s the optical design of pancake lenses became more complicated and the latest generation has overcome the limitations of traditional designs. As a result, pancake lenses are now also available in wide-angle and even short telephoto variations.

Due to the increasing demand for cameras with a compact form factor, pancake lenses are experiencing a second wave of popularity while having reasonable prices, which makes them accessible to a wide range of photographers. Such lenses are especially useful for those who enjoy travel photography.

Travellers' choice

Note

Among autofocus lenses designed for 35mm full-frame mirrorless cameras only. Speed of standard and telephoto lenses is taken into account.

Professional lens

One of the best ultra-wide angle prime lenses

According to lens-db.com; among lenses designed for the same maximum format and mount.

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You are already on the page dedicated to this lens.

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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.

MF

Sorry, no additional information is available.

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.

Non-retrofocus lens

The lens was designed for use with 35mm film SLR cameras with the mirror locked in the up position. The lens extended into the SLR's mirror box when mounted. Mirror lock-up must be activated prior to mounting the lens; otherwise its rearmost element would be in the way as the mirror flipped up and down during exposure. A separate optical viewfinder had to be mounted on the accessory shoe to confirm angle of view, because when the mirror is in the up and locked position, the subject is no longer visible through the viewfinder.

Closest focusing distance

The minimum distance from the focal plane (film or sensor) to the subject where the lens is still able to focus.

Closest working distance

The distance from the front edge of the lens to the subject at the maximum magnification.

Magnification ratio

Determines how large the subject will appear in the final image. For example, a magnification ratio of 1:1 means that the image of the subject formed on the film or sensor will be the same size as the subject in real life. For this reason, a 1:1 ratio is often called "life-size".

Electromagnetic diaphragm control system

Provides highly accurate diaphragm control and stable auto exposure performance during continuous shooting.

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.

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.