Leitz Wetzlar Telyt-S 800mm F/6.3

Super telephoto prime lens • Film era • Discontinued • Collectible

Features highlight

Drop-in filters
Built-in hood


Production details:
Production type:Small-batch production
Availability: Sold out
Order No.:11921
Original name:LEITZ WETZLAR TELYT-S 1:6.3/800
System:Leica R (1964)
Optical design:
Focal length:800mm
Maximum format:35mm full frame
Mount and Flange focal distance:Leica R [47mm]
Minolta SR [43.5mm]
Diagonal angle of view:3.1°
Lens construction:3 elements in 1 group
Diaphragm mechanism:
Diaphragm type:Preset
Aperture control:<No data>
Number of blades:<No data>
Closest focusing distance:12.5m
Magnification ratio:1:13
Focusing modes:Manual focus only
Manual focus control:Rack-and-pinion mechanism
Physical characteristics:
Weight:6860g (Leica R)
Maximum diameter x Length:⌀152×790mm (Leica R)
Filters:Removable front filters are not accepted
Additional features:Drop-in filter holder (Series VII)
Lens hood:Built-in telescopic round
Lens caps:14162 (rear)
Teleconverters:Leitz / Leica APO-Extender-R 1.4X → 1120mm F/8.8
Leica APO-Extender-R 2X → 1600mm F/12.6
Leitz / Leitz Wetzlar Extender-R 2x → 1600mm F/12.6
Sources of data:
1. Lenses for the LEICA R system booklet (PUB. 111-133).
2. Handbook of the LEICA system (PUB. 100-021) (May 1987).
3. Electronic-Leica R3 booklet (PUB. 121.111-104) (November 1977).
4. Leica R4-MOT booklet (PUB. 121.111-136) (August 1980).
5. Handbook of the LEICA system (September 1995).
6. Leica Catalogue (January 1979).
7. Leitz General Catalogue of Photographic Equipment (September 1978).
8. Handbook of the LEICA system (July 1982).
9. Handbook of the LEICA system (December 1989).
10. Handbook of the LEICA system (April 1981).
11. Leica M4-2 booklet (PUB. 121.110-108) (February 1978).

Manufacturer description #1

From the LEICA photography magazine (1970, No. 2):

Also shown at Photokina was a prototype 80mm f/6.3 achromat approaching apochromat qualities and characteristics. Special glass developed in the Leitz laboratories is used in the design of this 3-element lens giving it completely new image performance standards. Unlike many long focus lenses in this category, the new 800mm is not a mirror but a glass lens. It can be stopped down in the normal way by means of an iris diaphragm, without loss of aperture angle or abnormal reproduction of unsharp image areas. The 800mm will take its place as Leitz' longest focal length in time for the 1972 Olympics.

Manufacturer description #2

From the LEICA photography magazine (1973, No. 1):

The 800mm lens for the Leicaflex SL represents a new breakthrough in lens design. One of the fastest of extremely long focus lenses made, it utilizes a unique new glass developed by Leitz which reduces residual aberration and unsharpness to less than 1/3 of the values for normal optical glass, giving greatly improved contrast, resolution, and color differentiation.

The 800mm lens consists of one three-element group, with a 3 degree angle of field and focusing range of 41' to infinity. Its smallest aperture is f/32 and its smallest object field 12 5/8 x 18 7/8". A filter slot accommodates series 7 filters. The high-precision sport-finder gunsight aiming device is built into the lens carrying handle. The lens can be supported by a single sturdy tripod coupled to the tripod bushing located at the center of balance, however, an additional 1/4" tripod socket mounted in an auxiliary ring for optical use can be inserted when extra stability is needed. The lens weighs approximately 15 pounds and measures just over 31" in length and 5.9" in diameter. A styro-foam lined aluminum carrying case measuring 22" x 16" x 7 3/4" with molded compartments for a Leicaflex body, the three disassembled lens parts and the auxiliary tripod socket ring is supplied with the lens.

The 800mm Telyt-S with carrying case (Cat. #11921) is priced at $3,980.00.

Manufacturer description #3

The very long focal length lenses have, until now, experienced residual color abberations which became more prominent with increasing focal length. The use of crystalline optical elements such as calcium fluorite has heretofore been one of the most successful methods of reducing these errors; but the crystalline elements are more fragile than glass and have a rather high coefficient of thermal expansion, making them difficult to use. The new Leitz glass possesses the desirable qualities of the crystalline elements, without the shortcomings. This significant technical advance will be of particular interest to sports photographers, nature photographers, government, and space agencies who are the major users of extremely long lenses.

Weighing approximately 15 pounds and measuring just over 31" in length and 5.9" diameter, the 800mm lens consists of one three-element group with 3° angle of field and a focusing range of 41' to infinity. Smallest aperture is f/32; smallest object field is 12 5/8" x 18 7/8". The filter slot accommodates series 7 filters. A high precision sportsfinder gunsight aiming device is built into the lens carrying handle. While the lens can be supported by a single sturdy tripod coupled to the primary tripod bushing located at the center of balance, an additional 1/4" tripod socket mounted in an auxiliary ring for optional use, can be inserted when extra stability is required. Supplied with the lens is a styrofoam lined aluminum carrying case measuring 22" x 16" x 7 3/4", with molded compartments for the three disassembled lens parts, the auxiliary tripod socket ring, and a Leicaflex camera body.

Manufacturer description #4

For a long time, 400mm was the longest focal length in the LEICA and LEICAFLEX lens range; then about three years ago we introduced a 560mm lens. Now we are about to launch an unusually long focus system which is remarkably fast for its focal length: an 800mm f/6.3.

The new prototype will be available in time for the 1972 Olympic Games. Unlike most long focus lenses in this category which are mirror optical units, the 800mm is a glass system, and therefore - unlike mirror lenses - can be stopped down in the normal way with an iris diaphragm with no lost aperture angle or abnormal reproduction of unsharp image areas.

To appreciate this achievement it must be realized that lens systems of extremely long focal length are very difficult to develop. Residual color aberrations become more prominent with increasing focal length and the most modern way of correcting them is to use crystalline optical media. The drawbacks of such crystals is that they are chemically unstable and very sensitive to damage; in particular, their relatively high coefficient of thermal expansion makes them less suitable for large lenses.

The Ernst Leitz Glass Laboratory in Wetzlar carried on extensive research to produce various glasses of extreme optical characteristics. One result is a special glass closely resembling certain crystalline materials, but without their unfavorable properties. This special glass is mechanically and thermally stable and easy to work. With it, we designed a 3-element, 800mm lens of completely new image performance standard.

For the technically interested: A greatly reduced secondary spectrum not only gives this lens virtually apochromatic correction (negligible focus deviation in all three main bands of the spectrum), but, in fact, an overall optical performance even superior to normal apochromats. Residual aberrations and unsharpness were reduced to less than one-third of the values which are accepted with normal glasses. The result is improved contrast, detail resolution and color differentiation.

The new 800mm LEITZ prototype f/6.3 consists of 3 cemented lenses, with only 2 glass/air surfaces (coated, of course). As the lenses are relatively thin, light transmission of the system is exceptionally high. This, plus the reduced effect of light scatter, is particularly important when photographing very distant subjects where the image contrast is already reduced by atmospheric effects. The lens construction also uses far less glass than multi-lens systems. This concentration of high image illumination means shorter exposure times than for complex tele lenses with the same nominal aperture.

The 800mm is, of course, not just an experiment, but a development to fill a practical need. It is a special lens for the specialist photographer. With its 16-fold magnification (compared with the standard 50mm lens), it spans extreme distances to bring in picture subjects really close. At the same time, it compresses the image perspective of subjects at different distances - the typical telephoto effect which experienced photographers deliberately use for creative work.

Manufacturer description #5

The LEITZ 800mm TELYT-S f/6.3 is another superlatively color-corrected system based on our recently developed glasses with "anomalous partial dispersion", and provides performance superior to that of many apochromatic objectives. The lens consists of three elements cemented together to provide only two-air-glass interfaces, thus greatly reducing the problem of internal reflection and yielding long-range images of the highest contrast. Its optical quality is unexcelled in this focal length.

From the Popular Photography magazine (January 1971)

Photokina '70

Leitz also displayed an 800-mm f/6.3 prototype for an entirely new form of a long-focus achromat yielding unusually good color correction. This new Leitz achromat consists of a double convex positive lens cemented between two thin negative meniscus elements. The meat in this sandwich is a new and patented glass recently developed by the Leitz Glass Research laboratories in Wetzlar. The difference in this glass is its peculiarly non-linear change of light-bending power for light of different colors. This gives the lens designer a powerful new tool for bringing red, green, and blue rays together at nearly the same focal plane. Moreover, it is far less difficult to work than crystalline materials, such as fluorites, and has the resistance of a glass to atmospheric and other attacks to which the fluorites are sensitive.

Ordinarily, lens designers believe that with normal optical materials they can reduce the green-shift in relation to the common focus for red and blue rays to about 1/1,000 of the focal length. The new Leitz 800-mm f/6.3 achromat reduces this chromatic error to about 1/3 of this - that is, to approximately 1/3000. The result is a marked improvement in both contrast and resolution because all parts of the spectrum are brought more nearly to the same focus. In addition, the new lens has only two air-glass surfaces, which produce only a single reflection at a great distance from the film, thus eliminating image degradation by reflected light from optical or mechanical surfaces inside the lens.

Leitz states that the new 800-mm f/6.3 "special-glass" achromat is not yet in production, but that it will be ready for use by photographers at the 1972 Munich Olympics.

From the editor

The lens was announced at Photokina 1970 as Leitz Telecron with Leica R mount, issued for the 1972 Olympic Games and made generally available (to special order only) in 1973.

This lens was made possible by new types of glass by which the three-element symmetrical single component design yields high contrast, resolution and color differentiation with residual aberrations reduced to a minimum.

The barrel disassembles into five parts, that lock together with bayonet couplings. Central section of the lens is equipped with huge aluminum handle for transportation. The tube which attaches to the camera carries the preset diaphragm and a filter slot for Series 7 filters.

Focusing is by rack-and-pinion with a control wheel.

Two tripod sockets are provided, one at the point of balance and one at the front to provide extra stability.

The carrying handle incorporates a gunsight type aiming device for rapid alignment on the subject, which would be difficult on the focusing screen with an angle of view of only 3 degrees.

The lens was supplied in a fitted aluminium case.

According to LEICA, ROM modification is NOT possible.

Other super telephoto prime lenses in the Leica R system

Sorted by focal length and speed, in ascending order

Leica R mount (13)
Leitz / Leitz Canada / Leica Telyt-R 350mm F/4.8 [11915]A7 - 53.00mE77 1980 
Leitz Wetzlar / Leitz Canada / Leica Telyt-R 400mm F/6.8 [11903, 11906, 11960]M2 - 13.60m-- 1969 
Leica Novoflex Telyt-R 400mm F/6.8 [11970, 11926]M2 - 17.50m-- 1990 
Leitz Wetzlar / Leitz Canada Telyt-R 400mm F/5.6 [11866, 14146, 14137, 14154]P2 - 13.60m-- 1968 
Leica APO-Telyt-R 400mm F/4 Module System [11857]A9 - 72.15m-- 1996 
Leica APO-Telyt-R 400mm F/2.8 [11260]A11 - 94.70m-- 1992 
Leica APO-Telyt-R 400mm F/2.8 Module System [11847]A10 - 83.70m-- 1996 
Leitz Wetzlar / Leitz Canada / Leica Telyt-R 560mm F/6.8 [11907, 11906, 11865]M2 - 16.40m-- 1971 
Leica Novoflex Telyt-R 560mm F/6.8 [11971, 11927]M2 - 113.00m-- 1990 
Leitz Wetzlar / Leitz Canada Telyt-R 560mm F/5.6 [11867, 14146, 14137, 14155]P2 - 16.60m-- 1968 
Leica APO-Telyt-R 560mm F/5.6 Module System [11858]A9 - 72.15m-- 1996 
Leica APO-Telyt-R 560mm F/4 Module System [11848]A11 - 83.95m-- 1996 
Leica APO-Telyt-R 800mm F/5.6 Module System [11849]A11 - 83.90m-- 1996 

Lenses with similar focal length

Sorted by manufacturer name

Interchangeable mount (5)
Kowa Prominar 850mm F/9.6 FLM14 - 133.00m⌀95 2010 
Soligor 800mm F/8 (s/n 9xxxxxx) [T]P2 - 125.00m--
Tokina 800mm F/8 [T]P4 - 418.00m--
Vivitar 800mm F/8 Type 1 [T]P2 - 123.00m--
Vivitar 800mm F/8 Type 2 (s/n 37xxxxxxx) [T]P4 - 218.00m--
Notify of

Copy this code

and paste it here *

Inline Feedbacks
View all comments

Copyright © 2012-2024 Evgenii Artemov. All rights reserved. Translation and/or reproduction of website materials in any form, including the Internet, is prohibited without the express written permission of the website owner.

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.


Sorry, no additional information is available.


Sorry, no additional information is available.


Replacement rear cover for Leica R-mount lenses except 21mm.

Drop-in filter holder

A drop-in filter holder with a neutral filter comes with the lens. The holder accepts Series VII filters. The filter holder must be always in place because the filter is a part of the lens optical system.

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 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/6.3 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.