Nikon FM2

35mm MF film SLR camera

Specification

Production details:
Announced:1982
System: Nikon F (1959)
Format:
Maximum format:35mm full frame
Film type:135 cartridge-loaded film
Mount and Flange focal distance:Nikon F [46.5mm]
Shutter:
Type:Focal-plane
Model:Mechanical
Speeds:1 - 1/4000 + B
Exposure:
Exposure metering:Through-the-lens (TTL), open-aperture
Exposure modes:Manual
Physical characteristics:
Weight:540g
Dimensions:142.5x90x60mm

Manufacturer description #1

Proprietary technology in the development of shutter assemblies enabled Nikon to produce a world's first - vertical-traverse titanium shutter curtains with a slit travel time that is twice as fast as the shutter in any other 35mm SLR camera. It permits a top shutter speed of 1/4000 sec. with the FM2, as well as the fastest X-sync speed available for a camera of this type, 1/200 sec. The Nikon FM2 can stop action where a flash was once necessary. And the fast flash sync speed virtually eliminates ghost images caused at slower sync speeds, making synchro/sunlight photography easier than ever. Increasing the travel velocity of the FM2's shutter has one additional effect on camera performance. Closer tolerances on shutter timing at all high speeds.

The Nikon FM2 is a mechanical camera, requiring battery power only for the light meter and LED flash ready-light. It allows full manual control over shutter speed and aperture setting with quick and easy match-diode metering. Other features include interchangeable focusing screens, energy-saving meter switch, depth-of-field preview, self-timer, and Nikon's performance proven center-weighted metering. Like all Nikon cameras, the FM2 is constructed of the finest materials including an aluminum alloy body and back with brass top and bottom covers. Designed to stand up to professional use, the Nikon FM2 accepts the Motor Drive MD-12, Data Back MF-12 and all AI-Nikkor and Nikon Series E lenses.

Exclusive Shutter Design Provides 1/4000 sec.

In the Nikon FM2, a top shutter speed of 1/4000 sec. was achieved by reducing the weight and mass of the titanium shutter curtains. This permitted their travel velocity to be increased, a much more accurate way to achieve high speed than just using a narrower slit width. The specially treated titanium curtains are 58% lighter than conventional ones and utilize an etched honeycomb pattern to maintain strength and rigidity.

Interchangeable Focusing Screen

The standard Nikon K screen comprised of central split-image rangefinder spot, microprism collar, and matte/Fresnel outer field (12mm diameter reference circle denotes center-weighted metering area) can be removed by pressing the small latch at the top of the mirror box. The optional Type B screen has a 12mm fine ground matte focusing spot for close-up or telephoto work and the E screen shows a grid of vertical and horizontal lines which is well suited for copy work and architectural photography. (The same screens may be used in the Nikon FE.)

Full Information Viewfinder

Viewfinder shows 93% of the actual scene with excellent centering, an important asset for good composition. The selected shutter speed and aperture are shown with accurate LED match-diode metering. The LED exposure display lights in five different combinations for precise manual metering.

Depth-of-Field Preview

Conveniently located lever may be pushed to stop down lens for previewing actual depth-of-field dunng full aperture metering. Also used for stop down metering for non-meter coupled lenses.

Hot Shoe / Flash Ready LED

The hot shoe on the Nikon FM2 has an extra electrical contact which transmits a signal between camera and flash. When used with the Nikon Speedlight SB-E, SB-10 or SB-15, the LED lights to mdlcate the flash is recycled and ready to fire. If the FM2 is inadvertently set at a shutter speed faster than the top X-sync of 1/200 sec., the LED blinks to warn the user when the SB-15 or other dedicated Nikon Speedlights are used.

Shutter Speed / ASA-ISO Dial

FM2 provides mechanically-timed shutter speeds from 1-1/4000 sec., plus "B" for time exposures. Knurled shutter speed dial can be lifted to set film speed from ASA/ISO 12-6400 the widest range in its class to accommodate special emulsions and push-processing film for higher light sensitivity.

Energy-Saving Meter Switch

The FM2's shutter release button is threaded to accept a standard cable release; also functions as a meter-on switch. Depressed halfway, it turns on the viewfinder LED display. The meter shuts off automatically approximately 30 sec. after pressure is removed from the shutter release button.

Self-Timer

Mechanical self-timer provides 10 sec. firing delay, and may be cancelled. In addition, when the self-timer is activated, the mirror immediately goes up, eliminating any chance of camera shake during critical close-up or long telephoto shooting.

Multiple Exposure Lever

Lever adjacent to film advance disengages transport mechanism for intentional multiple exposures. Excellent position allows for convenient motor-driven multiple exposures as well with precise frame registration. Frame counter doesn't advance.

Manufacturer description #2

If you want manual focus and manual exposure control, here's the way to get it - with proven Nikon performance and durability. The FM2N is the choice of traditionalists everywhere.

YOU'RE IN COMMAND

The FM2N is a camera that puts you in charge. Using 60/40 center-weighted metering, you select the aperture, you select the shutter speed, to create the type of photographs you're looking for.

LEGENDARY NIKON PERFORMANCE AND DURABILITY

Like all Nikon F cameras, the FM2N is made to exacting standards with durable die-cast metal body construction and precision operating features. Vertical-travel aluminum alloy shutter curtains offer reliable, consistent performance. A mirror shock absorber virtually eliminates mirror bounce or shake that might blur some exposures. Four ball-bearing clusters and reduced film winding torque assure silky-smooth film advance.

3-POINT LED EXPOSURE DISPLAY

In addition to shutter speed and aperture, a 3-point exposure display appears in the viewfinder. It instantly tells you if your exposure is over (+), under (-) or right on (0).

MOTOR DRIVE MD-12

Attach the optional Motor Drive MD-12 to the FM2N, and you're into motor drive photography. Shoot single frames or try sequential shooting at up to 3.2 frames per second.

DATA BACK MF-16

Record year/month/day or day/hour/minute or any 2-digit number on your photographs. Perfect for scientific or research photography. LCD quartz clock ensures precision information.

F LENS MOUNT

Because the FM2N incorporates Nikon's F lens mount, it uses all of Nikon's current lenses, and hundreds of previous lenses.

OTHER NIKON ACCESSORIES

The FM2N also accepts a wide range of other Nikon accessories, including the Modulite Remote Control Set ML-2, Intervalometer MT-2, Wireless Remote Control Set MW-3, Battery Pack DB-2, Nikon Speedlights and close-up accessories.

NEW TITANIUM BODY FM2T

If you're going to extremes to get a great photograph, consider the new FM2T version of the FM2N. Made with an incredibly strong titanium outer shell, this camera is highly shock and corrosion resistant. All other specifications and features are the same as the FM2N.

Manufacturer description #3

TYPE OF CAMERA: 35mm single-lens-reflex (SLR)

PICTURE FORMAT: 24mm x 36mm (standard 35mm size)

LENS MOUNT: Nikon bayonet mount

LENSES: Nikon/Nikkor AI lenses; Non-AI lenses cannot be mounted

SHUTTER: Vertical-travel, metal, focal plane, mechanical shutter with titanium curtains

SHUTTER RELEASE: Mechanical; center-threaded shutter release button accepts AR-3 Cable Release; button locked when film advance lever is flush with camera body

SHUTTER SPEED SETTINGS: 1/4000 sec. - 1 sec. X200 (1/200 sec.), B (Bulb)

FILM ADVANCE LEVER: Single-stroke type; 30° stand-off angle and 135° winding angle

SELF-TIMER: Set/cancel mechanical type provided; approx. 10-sec. shutter release delay

VIEWFINDER: Eye-level pentaprism type; 0.86X magnification with 50mm lens set at infinity; finder coverage approx. 93% of picture field

VIEWFINDER DISPLAY: Shutter speed, ADR (aperture-direct-readout) f/stop in use, and five different LED exposure displays using "+", "o" and "-" signs

FOCUSING SCREEN: Split-image microprism type (Type K) provided as standard; matte type (B) and matte with horizontal and vertical line etchings (E) also available; screens usable with Nikon FE

REFLEX MIRROR: Automatic quick-return type incorporating special control gear and wheel-and-brake mechanism for reduced vibration and noise; non-lockable type

DEPTH-OF-FIELD PREVIEW: Provided

MULTIPLE EXPOSURE LEVER: Provided; disengages frame counter for correct count

FRAME COUNTER: Additive type (S.O.-36); automatically resets to "S" when camera back is opened

FILM REWIND: By crank provided after film rewind button is pressed

FLASH SYNCHRONIZATION: Built-in ISO-type hot-shoe; threaded sync cord terminal provided for off-camera or multi-flash photography; synchronization with electronic flash units at speeds up to 1/200 sec.

FLASH READY-LIGHT: LED provided; visible inside viewfinder; lights up when SB-15, SB-10 or SB-E Speediight unit used is fully charged; blinks to warn that the shutter speed set is beyond the electronic flash's sync range when the SB-15 or other dedicated Nikon Speediights are used

EXPOSURE METERING: Through-the-Iens center-weighted full aperture exposure measuring system using a pair of SPDs (silicon photo diodes) and metering monolithic IC circuit

METERING RANGE: EV 1 to EV 18 at ASA/ISO 100 and with f1.4 lens (i.e., from 1 sec. at f1.4 to 1/1000 sec. at f16)

FILM SPEED SETTINGS: ASA/ISO 12 - ASA/ISO 6400

POWER SOURCE: Choice of one 3V lithium battery, two 1.55V silver-oxide batteries, or two 1.5V alkaline-manganese batteries; optional Anti-Cold Battery Holder DB-2 accepting two AA-type penlight batteries available

EXPOSURE METER SWITCH: Light pressure on shutter release button switches meter on; meter stays on for approx. 30 sec. after finger leaves button, then automatically switches off; meter automatically turned off when shutter speed dial is set at X200 or B

BATTERY CHECK: LED exposure display inside viewfinder lights up when exposure meter is switched on if there is sufficient power (i.e., shutter speed dial is set anywhere except "X200" and "B")

CAMERA BACK: Opens by lifting the film rewind knob as the camera back lock is pushed counterclockwise; detachable and interchangeable with Data Back MF-12; memo holder provided

Special limited editions (1)

Similar cameras (4)

35mm full frame • Manual focus • Film • Singe-lens reflex • Nikon F mount

Model Shutter Metering Modes Year
Kiev-17 M, 1/1000 -- M 1978
Kiev-19 M, 1/500 TTL • WA M 1985
Kiev-19M M, 1/500 TTL • OA M 1988
Kiev-20 M, 1/1000 TTL • OA M 1983
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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, Leica, Nikon, Pentax, Sony etc.) are always incompatible. In addition to the mechanical and electrical interface variations, the flange focal distance (distance from the mechanical rear end surface of the lens mount to the focal plane) is also different.

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 lens element 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.