Bronica S2

Production status
Bronica system cameras

Bronica S2

Medium format MF film SLR camera • Discontinued


Medium format 6x6
Film type:
120 roll film
220 roll film
Bronica [102mm]
1 - 1/1000 + B, T
Exposure metering:
Exposure modes:
Physical characteristics:

Manufacturer description #1

The new Bronica S2 doesn't really offer very much over any other 2 1/4 square single lens reflex if you leave out the automatic return mirror, the automatic reopen diaphragm, interchangeable film backs, interchangeable Nikkor lenses, and high speed focal plane shutter.

But why leave them out when they add so much to operating ease and performance. And it costs you no more to enjoy them. Bronica S2 with 75mm Auto-Nikkor f2.8 lens is $479.50.

If you must leave something out, consider the Bronica C. Costs you $100 less. Substantially the same as the S2, except it doesn't have interchangeable film backs. Has interchangeable film inserts, though, like the S2, which handle 220 as well as 120 roll film.

Manufacturer description #2

After the new Bronica C, what could we do for an encore?

The new deluxe Bronica S2 with interchangeable film backs.

The new S2 is everything you'd expect a Bronica to be: versatile, responsive, reliable - a 2 1/4 square reflex that hangles with the ease and speed of a fine 35.

Like the Bronica C, it has an automatic mirror and automatic diaphragm system, features not generally found in other large-format single lens reflexes. The film-shutter wind can be operated by rapid crank or ratchet-action knob. There is a depth-of-field previewer, an interchangeable viewing hood, and focal plane shutter but with speeds to 1/1000th second. Also, like the Model C, it accepts the new 220 film as well as 120.

But, where the Bronica C has a fixed back with interchangeable film inserts, the new S2 has a removable back that lets you change films even in mid-roll. The Filminder feature provides automatic safeguards against double exposures and blanks. Both Bronica C and S2 use the same interchangeable Auto-Nikkor lenses: 50mm f3.5, 75mm f2.8, 135mm f3.5, 200mm f4, 400mm f4.5 and 600mm f5.6, plus a wide array of accessories.

Price of the Bronica C with 75mm Auto-Nikkor f2.8 is $379.50, the new S2, $479.50. Additional S2 backs are $109.50 each.

Manufacturer description #3

Doesn't every slr have an automatic return mirror?

You'd think so, by now. It's almost 10 years since it was developed.

The automatic mirror eliminated finder blackout, one of the major drawbacks in early slr design. It also enabled the development and use of automatic-diaphragm lenses. It gave the single-lens reflex a responsiveness it had never known - a new ease and speed of handling. There isn't a 35mm slr of any consequence without this important feature.

Yet, of the two 2 1/4 square slr makes, currently available, only one is equipped with an instant return automatic mirror. Only Bronica seems to recognize that finder blackout is an anachronism, totally inconsistent with modern slr camera design.

If you're moving up to a 2 1/4 square single-lens reflex, move all the way up to Bronica. Enjoy all the benefits of modern automatic design and system versatility. Enjoy the incomparable quality of Nikkor optics.

There are two Bronica models: the S2 and C. The S2 accepts interchangeable film backs, whereas the model C has a fixed back. The two are very much alike in all other respects. The S2 is priced at under $480 with 75mm Auto-Nikkor f2.8 lens, and the C, at under $380, similarly equipped.

Both models use the same interchangeable Nikkor lenses, and draw upon the same system of interchangeable attachments and accessories.

Manufacturer description #4

Ever get the feeling you're being followed?

Every newly announced 2 1/4 square SLR will be comin thru with automatic mirror

Who, in this day and age, would expect any SLR user to put up with the inconvenience of finder image blackout?

It's 8 or 9 years since the automatic return mirror was developed. And today there isn't a single 35mm SLR worth its salt without it. Aren't the advantages as important in 2 1/4 square? Of course!

Bronica pioneered the automatic mirror system in the 2 1/4 square format and, as of now, offers the only 2 1/4 square SLR without finder blackout. Even after the new ones join the field, the Bronicas will still be the only ones using Nikon lenses. And that's pretty hard to beat.

If you're moving up to 2 1/4 square format, there is a clear advantage in the superior optics, features and system versatility offered by Bronica.

There are two models to choose from: the S2 with interchangeable film back, and the C with fixed back, $479.50 and $379.50, respectively, each with 75mm Auto-Nikkor f2.8 lens. Both use the same interchangeable Nikkor lenses, and draw upon the same system of attachments and accessories.

Manufacturer description #5


The Bronica S2 followed the S in 1966 and incorporated a number of new features. The primary change was the switch to a removable helical type focusing mount. Identifying points are:

1. Removable helical (rotating) focusing mount has black knurled knob for focusing on front of camera body.

2. No distance scale or focus control on advance knob.

3. Small release button for focus ring on front of body.

4. No mirror lock switch on bottom of body.

5. Body now available in black or chrome.

6. PC contact now on left side of body.


With the change in design to a front helical focusing mount, the accessory systems for Bronica were also changed.

All Bronica Nikkor and Zenzanon lenses fit the S2, including the large bayonet 105mm and 300mm. The focusing tube for the Tele-Nikkors is the current (#81505) unit.

All prisms, hoods, grips, etc. that fit the current S2A will fit the S2.

Manufacturer description #6

The Zenza Bronica S-2 is the ultimate single lens 6X6 reflex camera, designed to add improvements to the S type and C type. This new camera accepts both standard 120 size film and the new 220 size film. The noted Nikkor lenses are equipped with instant return automatic diaphragms. A full line of accessories is available for this camera. The Zenza Bronica S2 is a supreme camera both in name and reality.

Instant Return Automatic Mirror

The reflex mirror of Bronica Model S2 is an exclusive and original mechanism. It is very different from that of other single lens reflex cameras. Usually mirrors move upward, but the Bronica instant return automatic mirror moves forward and down. After the exposure, it instantly and automatically returns to viewing position.

Thus, it is possible to use wide-angle and large caliber lenses, and a bright image remains on the ground glass except while the shutter is in motion.

Interchangeable 'Filmfinder' Back

This convenient feature offers many advantages. It is possible to change film in the middle of a roll (black-and-white to color, color to black-and-white, indoor to daylight, etc.) without the loss of a single exposure. It permits you to preload several backs and shoot continuously without stopping for reloads.

The filmfinder back is fully automatic and foolproof. It is equipped with a metal dark slide to prevent the film from being exposed while the back is off the camera. The back cannot be removed until the dark slide is inserted and while the back is off the camera, the dark slide cannot be withdrawn.

When a filmfinder back is attached to the camera, no attention need be paid as to whether the film or the shutter has been previously wound.

The film advance crank, which normaly winds the shutter and the film simultaneously, automatically performs only the required function. For example, if the shutter is wound and if the film in position has been exposed, turning the crank will only advance the film to a fresh unexposed section. Also, when the back is on the camera, the dark slide must be completely withdrawn before an exposure can be made.

Exclusive Nikkor Lenses and Automatic Diaphragm

Nikkor lenses are especially designed for Bronica Cameras and can be used with C type, and S type. You can speedily adjust the focus of the bright image; These lenses (50mm, 75mm, 135mm, 200mm and 400mm) have instant reopening automatic diaphragms.

Depth-of-Field Preview Button

By pressing this depth-of-field preview button, you can check the depth-of-field before exposing.

Switch Lever for 24 Exposures

Ordinary 120 film gives 12 exposures. 24 exposures are possible on the new 220 size film.

The Bronica Model - S2 has an entirely new system permitting either length to be used.


TYPE: 2 1/4 X 2 1/4" (6cm X 6cm) Single lens reflex camera.

FILM: 120 roll film, 12 exposures and 220 roll film, 24 exposures.

INTERCHANGEABLE FILM: Interchangeable film back fully coupled with camera body, dark slide with safety lock system, built-in leak prevention curtain.

STANDARD LENS: Nikkor 75mm F2.8 fully automatic preset diaphragm, 4 group 5 element.

LENS MOUNT: Bayonet type (BRONICA mount), also equipped with screw mount (57mm X 1mm pitch), large bayonet mount for long telephoto lenses.

FINDER: Fresnel lens and large magnifier.

VIEWFINDER HOOD: Interchangeable with pentaprism viewfinder or magnifying hood.

FOCUSING: Helicoid type, stroke 14mm, rotating angle of focussing ring 250°.

DISTANCE SCALE: For 75mm, 50mm, 135mm and 200mm lenses.

MIRROR: Flip down, instant return, automatic mirror system.

DIAPHRAGM: Fully automatic diaphragm - 75mm, 50mm, 135mm, 200mm and 400mm lens.

DEPTH-OF-FIELD PREVIEW: Depth-of-field can be checked by pressing preview button.

SHUTTER: Vertically operating focal plane shutter, non-rotating single shutter dial, B, 1, 1/2, 1/4, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000 and "X" (1/40), "T" (Time) shutter release lock device. Intermediate shutter speeds.

SYNCHRO: Automatic switch-over synchronization system.

FILM LOADING: Separate film holder, automatic film winding system by matching with film start mark.

FILM WINDING: Winding crank or knob.

FILM COUNTER: Automatically returns to "0".

CAMERA BODY: Made of 18-8 Stainless Steel, bright polished finish.

Manufacturer description #7


In 1969, the S2 was replaced with an internally modified version, identified as S2A. Since there were almost no external changes, this model is identified by the designation S2A following the serial number.

In 1973, a minor change was made in the neckstrap studs, altering them so that they would accept the same neckstrap as the EC model. At that time, the S2A marking after the serial number was dropped. New series S2A cameras without the S2A marking start with body number 150037.

This model is now current and accepts all Auto-Nikkor lenses, Zenzanon lenses and Tele-Nikkors with #81505 focusing tube. All current accessories fit the S2A except those specifically limited to the DeLuxe, "S" or EC.

Manufacturer description #8

Except for the redesigned film/shutter crank and the engraved model identification, the Bronica S2A appears to be identical to the S2. Actually, it contains literally hundreds of internal changes and improvements that make the S2A the most reliable as well as the most versatile camera for professionaI 2 1/4-square sIr photography.

All the unique advantages Bronica brought to this format are retained in the S2A. Among these are automatic mirror and diaphragm action, interchangeability of lenses, film backs and finders, and synchronized shutter speeds to 1/1000th second. The built-in shutter and extra-large lens mount make it easy to fit the Bronica with hundreds of lenses made for other cameras, from 35mm to 4x5 models, at moderate cost. The S2A accepts all current lenses and accessories in the Bronica system.

Manufacturer description #9

In the S2A, the innovating basic Bronica design has been refined to provide the highest degree of performance quality and reliability. Embodying literally hundreds of internal changes and improvements, the S2A blends rugged, professional durability with the speed and responsiveness of a fine 35.

All the unique advantages Bronica brought to the 2 1/4 x 2 1/4 format are retained in the S2A. It offers automatic mirror and diaphragm action for a constantly bright finder image, plus full interchangeability of lenses, film backs, and finders. The built-in focal plane shutter is uncannily accurate all the way to 1/1000th second. And, because it's built into the camera, there's no need to buy another shutter with every additional lens. In fact, prices of Bronica lenses and accessories, as well as the S2A itself, are substantially below their counterparts for other high-quality 2 1/4 x 2 1/4 sIr's.

With its unique combination of reliability, versatility and honest value, the Bronica S2A and its system unquestionably represent today's outstanding investment for professional 2 1/4 x 2 1/4 sIr photography.

Manufacturer description #10



Choose any of four automatic wide-angle lenses to fit your Bronica: New 40mm Auto-Nikkor f4, 50mm Auto-Nikkor f3.5, 45mm Auto-Komura f4.5 and 50mm Auto-Komura f3.5. All use the camera's built-in focal plane shutter.


For waist-level viewing, there's the standard folding hood or 5X Magnifying Hood. For eye-level shooting, choose Prism Finder "A" or open-frame Sportsfinder. A further choice is Prism Finder "C" with 30° inclined eyepiece.


There are eleven "long" lenses in the Bronica system, from 100 to 600mm focal length. All but three are automatic, including three Auto-Nikkors. Here, too, no extra shutters are required. Furthermore, you can double the focal length of any of these lenses with the Komura 2X Telemore.


Depending on which close-up accessory is best for you: bellows attachment (lets you focus from infinity to macro range with most lenses), extension tubes or lenses reversing ring. Use them separately or in combinations.

And that isn't all. Because the shutter is built into the body, you can fit the Bronica with virtually any lens made for larger-format cameras and many 35mm lenses, too, at surprisingly low cost.

You start with the very latest 2 1/4-square single-lens reflex - the new, automatic Bronica S2A. Designed to professional specifications and built for reliable performance, it offers every facility for advanced photography:

  • Auto-return mirror and auto-reopen diaphragm, eliminating finder blackout.
  • Shutter speeds from 1 second to 1/1000th, flash synch'd all the way.
  • Interchangeable film backs: roll film 2 1/4 x 2 1/4 or 2 1/4 x 1 5/8, and Polaroid.
  • Use of 120 or 220 film in same backs with auto-reset counters for both.
  • Depth-of-field previewer (lens reopens automatically when preview button is released).
  • Finder screen shows picture areas proportionate to 8x10/10x8 enlargements, makes accurate composition easy.

With all these and many more advantages, Bronica is priced far below any other fine 2 1/4-square slr. In fact, you can start out with a Bronica S2A and two lenses for less than the cost of a comparable camera with normal lens alone. And, since you don't have to pay for another shutter every time you buy another lens, you can build up your Bronica outfit that much faster.

When it comes to down-to-earth picture capabilities, the Bronica system provides more than you're ever likely to need.

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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 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 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 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.


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 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 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.


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.


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.


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.


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 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),


CF – crop-factor of a sensor,
FL – focal length of a lens.


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.


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.


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.


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 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.