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Exakta Varex IIb

aka Exakta VX IIb

35mm MF film SLR camera

Specification

Production details:
Announced:1963
System:● Exakta (1936)
Format:
Maximum format:35mm full frame
Film type:135 cartridge-loaded film
Mount and Flange focal distance:Exakta [44.7mm]
Shutter:
Type:Focal-plane
Model:Mechanical
Speeds:12 - 1/1000 + B, T
Exposure:
Exposure metering:None
Exposure modes:Manual
Physical characteristics:
Weight:695g
Dimensions:150x92x50mm

Manufacturer description #1

EXAKTA Varex IIb, 24x36mm, the supreme development of 35mm reflex photography, for the most exacting work

  • Simple to operate.
  • Subject selection, image framing and focusing by means of the brilliant, magnified reflex image; interchangeable viewfinders: Finder Hood giving an upright image, Penta Prism for an upright and laterally-correct image, Lens Magnifier Stereo View Finder "Stereflex". In place of the ground-glass screen, the Distance Meter (a split-image rangefinder centered In a ground-glass field) is a useful focusing aid with Finder Hood, Penta Prism, or Lens Magnifier; alternatively there is the image-brightening Fresnel Lens (a uniformly brilliant ground-glass screen with split-image rangefinder). Through- the-lens focusing, ensuring uniformity between reflex image and final picture and complete freedom from parallax.
  • Interchangeable lenses with fully-automatic spring or pressure diaphragms. Special-purpose lenses with focal lengths from 20 to 1000 mm can be employed with no limitations whatsoever; lenses from 20 to 180 mm focal length have fully-automatic spring or pressure diaphragms. World-famous quick-change bayonet lens mount.
  • Focal-plane shutter with rapid-wind lever and speed-setting knobs for shutter speeds from 1/1000 sec up to 12 seconds (internationally recognized shutter-speed sequence: 1/1000, 1/500, 1/250, 1/125, 1/60 sec. etc.); B and T settings for brief or long time exposures. Delayed-action selftimer release for shutter speeds from 1/1000 to 6 sec. Body shutter release with cable release thread; release lock, shutter tensioning and film advance mechanisms are interlocked to eliminate double exposures and blank frames. Three flash contacts (FP, F, and X) for all flash bulbs and electronic flash units.
  • Ever-dependable film advance mechanism; the film is either wound on to the take-up spool and back into the cassette (with rewind crank) or advanced from one cassette to another. Hinged camera back with film pressure plate to ensure perfect image definition. Frame counter. Film-speed indicator. Film-advance control disc. Film cutting knife.
  • Elegant, easy-to-handle light alloy body with durable covering. External metal components chrome-plated and enamel-finished.
  • Most comprehensive range of accessories to cover even the most unusual assignments. No restrictions on the use of close-up equipment.

The EXAKTA Varex lIb is normally supplied with Finder Hood (with Distance Meter or Fresnel Lens if requested) and one of the following lenses: Domiplan f 2.8/50 (FAD), Jena T f 2.8/50 (FAD), Jena Pancolar f 2/50** (FAD), Domiron f 2/50*** (FAD).

FAD = Fully-automatic diaphragm.

** With automatic depth-of-field indicator.

*** With extra-long helical focusing mount for taking close-ups down to 13 1/2 inches without special accessories.

Manufacturer description #2

Highly developed but not over-elaborated: that's the EXAKTA Varex IIb. Despite its fantastically wide field of operation it remains delightfully simple to operate; its ease of handling will be a welcome surprise to inexperienced beginners and the most exacting expert alike. This is a camera which can be adapted to perform almost every photographic task imaginable; with 30 years of constant evolution behind it, even in its present stage of highly developed perfection it still remains true to the basic design principle of all EXAKTA cameras: parallax-free reflex focusing. With a single glance into the reflex viewfinder and the minimum of control settings, you can be certain of obtaining a photograph with the sharpest possible definition, optimum depth of field and superb pictorial quality. Right from your very first trial exposures you will see the superiority of the EXAKTA method: your pictures will be better composed, and give you far more pleasure than ever before. No mater what type of work you do with your EXAKTA Varex, you can always be absolutely certain that the final picture wil be identical to the viewfinder image, since both are produced by one and the same lens. You will never lose part of the picture through differences in lens coverage; whatever you see in the reflex finder, will be there in the finished photograph. This invaluable quality will of course be all-important for taking close-up pictures and photomicrographs, when using special lenses and other accessories; there will be no need to use costly optical focusing aids, since the picture can always be framed and focused accurately in the reflex viewfinder.

Simplicity and economy: these are the two cornerstones on which the world-wide leadership of the EXAKTA system is based. The constant painstaking development of the EXAKTA system is your guarantee that your EXAKTA Varex camera and all its accessories wil remain proof against obsolesence and depreciation throughout the years to come.

Interchangeable viewfinder systems

Among the many advantages of the EXAKTA Varex Ilb are its interchangeable viewfinder systems. For particular types of work, the familiar waist-level Finder Hood can be detached with a single operation and replaced by the Penta Prism, the Lens Magnifier or the "Stereflex" Stereo View Finder. It is also possible to adapt the focusing system perfectly to the work in hand by exchanging the focusing screen itself.

Finder Hood: Ground-Glass Screen and supplementary magnifier together give x6 magnification of reflex image, providing speedy and accurate focusing for maximum definition. Brilliant, upright reflex image, easily viewed with both eyes. The Finder Hood should be used for all subjects which are not moving rapidly, those situated below eye-level and for taking pictures from a tripod, Repro Unit or similar fixture or through a microscope.

Penta Prism: This gives a x4-magnification, upright and laterally-correct image when the camera is held both horizontally and vertically. The camera is used at eye-level, for sighting the subject directly. Moving subjects move in the same direction in the Penta Prism as they do in reality, making this the ideal viewfinder for all types of action photography (especially when "panning" the camera to follow very rapidly moving subjects). Accessories: flexible Eyepiece Cup for shielding eyepiece against straylight, also designed for fitting vision-correcting lenses (a useful aid for spectacle wearers); Accessory Shoe for attaching supplementary equipment.

Fresnel Lens with split-image rangefinder

The viewfinder systems of the EXAKTA Varex (with the exception of the Stereo View Finder) can be provided with a Fresnel-Lens Focusing Screen to give increased image brightness, in place of the standard magnifying Ground-Glass Screen. The Fresnel-Lens Screen also has split-image rangefinder in the centre of a uniformly-brilliant ground-glass ring, making focusing twice as easy and accurate. This feature is particularly valuable in poor lighting conditions and for users who wear glasses. When the half-images in the rangefinder field are displaced = image out of focus, half-images accurately aligned above and below or alongside each other = correct focus. The wide ground-glass ring surrounding the rangefinder provides an additional means of focusing.

Focal-plane shutter with extra-wide range of speeds

The success of a photograph depends very largely on the camera shutter. This is why the EXAKTA Varex IIb has a focal-plane shutter, which is unequalled for reliability and the range of speeds to which it can be set. Here are a few of its particular advantages:

Two clearly-marked setting knobs for selecting speeds from 1000 sec to 12 seconds (standard sequence of speed-settings), T and B settings for time exposures. Sound-damped speed-adjusting mechanism. Built-in delayed-action release operating on speeds from 10 sec to 6 seconds. Rapid-wind lever. Easy-to-operate release button on camera body, with cable-release thread and release lock. Shutter mechanism exceptionally well protected against vibration and temperature fluctuations. Three-position flash-synchronization selector: F contact for fast-burning miniature flashbulbs (shutter-speed setting 1/30 sec), FP contact for ful synchronization with long-peak flashbulbs and faster shutter speeds, X contact for electronic flash units (shutter-speed setting 1/60 sec) and normal flashbulbs (shutter speeds of 1/8 sec or slower).

Ever-reliable film advance

In a miniature camera it is always important to keep the film lying absolutely flat and to ensure that it is advanced accurately and under full control. See how the EXAKTA Varex provides complete assurance on all these points: negative size 24 mm x 36 mm, on perforated 35 mm film. Camera body and film track form a single light-alloy casting, giving complete rigidity and reliability in operation. It is impossible for the film-bearing surface ot go out of adjustment. Accurately-machined film track and pressure plate to ensure maximum definition. Film either advanced from one cassette to another, or rewound after exposure by means of the rewind crank: both operations can be controlled and their progress observed from outside the camera. Frame counter, cutting knife for cutting the film with the camera closed for removing part of the film before the full length is exposed. Film-type reminder disc to remind you what type of film is in the camera. No unexposed blank frames or accidental double-exposures: interlocked film transport and shutter tensioning. Intentional double-exposures can however be taken for trick photography. Hinged (but completely removable) camera back with secure locking catch.

Concerning the general equipment and finish of the EXAKTA Varex IIb, the following brief details must suffice: carefully-shaped, easy-to-handle body; highly durable covering; exposed metal parts chrome-plated and lacquered. Tripod bush with broad bearing surface; carrying-strap eyelets.

Lenses with a world-wide reputation

The EXAKTA Varex uses only lenses made by internationally-famous manufacturers, conforming to the very latest developments in optical and mechanical technology and capable of mastering the most exacting assignments. Here are just a few of their qualities:

Ultra-sharp definition, correct colour rendering and high light transmission. Quick-change bayonet mount, allowing the standard lens to be removed with a single turn of the wrist and replaced by any of the numerous special-purpose lenses. Precision-machined helical focusing thread; depth of field scale (and also automatic depth of field indicator on Jena Pancolar lenses). Anti-reflection surface coating on lens elements.

The latest diaphragm-control mechanisms make it possible to focus the lens at full aperture in order to obtain the brightest possible screen image, and then to stop down to any previously-selected taking aperture without removing the camera from your eye. With lenses fitted with fully-automatic spring or pressure diaphragms, this operation is performed quite automatically the moment before the shutter is released. This saves a tremendous amount of time when taking pictures, besides making it impossible to forget the all important operation of stopping-down the lens. Lenses with fuly-automatic diaphragms can also be switched over to normal aperture setting when desired.

From the Modern Photography magazine (December 1966)

A quick visual comparison between the Model I Exacta (1936 version) and the today's VX-IIb would reveal a striking resemblance, outwardly at least. It certainly is a credit to the original camera that the design has been able to accomodate so many of today's necessary SLR features, such as interchangeable pentaprism and waist-level finders and automatic diaphragm, while retaining special Exakta features not duplicated on other SLR's, such as the fantastic number of shutter speeds and the built-in film knife.

A careful examination of the Exakta VX-IIb indicates that the basic mechanics of the IIa and its quality of construction have been retained - the fast shutter speed dial revolves during exposure: slow speeds are set on a separate dial which must be wound separately before each exposure: both the 300° single-stroke, non-geared rapid-wind lever and front shutter release are located on the left side of the trapezoidal camera body. It does not have an instant-return mirror.

The IIb, however, differs from previous Exaktas in having a folding rewind crank on the bottom of the camera, shutter speed markings in modern mathematical sequence (1/8, 1/15, 1/30, 1/125 instead of 1/25, 1/50, 1/100, etc.) and interchangeable prism which can be lifted off without depressing a catch. The faceplate, shape of the prism housing and markings of the slow speed dial have also been modernized and all control knobs are now heavily knurled for better handling. The view through the finder, now aided by a Fresnel lens, is bright with a large positive split-image rangefinder plus a fine ground-glass collar as a welcome additional focusing aid. Old-time Exakta users who were annoyed that focus in the center area didn't agree with focus at the edges will be happy to learn that the focus is now equal over the entire finder area.

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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.