Vivitar Series 1 600mm F/8 VMC Solid Catadioptric

Super telephoto prime lens • Film era • Discontinued

Abbreviations

VMC Multi-layer anti-reflection coating is applied to the surfaces of lens elements. This anti-reflection coating increases light transmission, eliminates flare and ghosting, and maintains color consistence among all lens models.

Features highlight

T
M/R
MF
Fixed

Specification

Production details:
Announced:1975
Production status: Discontinued
Original name:Vivitar Series 1 600mm 1:8 VMC SOLID CATADIOPTRIC LENS
System:-
Optical design:
Focal length:600mm
Speed:F/8
Maximum format:35mm full frame
Mount and Flange focal distance:Interchangeable mount (T)
Diagonal angle of view:4.1° (35mm full frame)
Lens construction:9 elements in 7 groups
Diaphragm mechanism:
Diaphragm type:Fixed
Aperture control:None
Focusing:
Closest focusing distance:7m
Magnification ratio:<No data>
Focusing modes:Manual focus only
Manual focus control:Focusing ring
Physical characteristics:
Weight:1360g
Maximum diameter x Length:⌀106×84mm
Accessories:
Filters:Removable front filters are not accepted
Rear screw-type 35.5mm
Lens hood:Screw-type round
Teleconverters:<No data>
Sources of data:
1. Manufacturer's technical data.
2. Vivitar Series 1 booklet (August 1976).

Manufacturer description #1

The development of Vivitar Series 1 Solid Catadioptric Telephoto Lenses represents a significant achievement in U.S. manufactured premium optics. Working in conjunction with the U.S. optical firm of Perkin-Elmer Corporation, Vivitar has incorporated the finest characteristics of intricate astronomical optics into a line of consumer and industrial lenses priced within reach of the advanced amateur or professional photographer.

With the introduction of Vivitar Series 1 Solid Catadioptric Telephoto Lenses, Vivitar and Perkin-Elmer have made optical technology previously applied only in space exploration and other highly advanced sciences, available to the general public. The incredibly compact size is achieved using spherically shaped lens elements which are pieced together to form virtually a single solid element. This unique process results in three outstanding benefits for the photographer. First, the lens maintains its precise optical alignment throughout extreme temperature variations allowing you to move from freezing to blistering climates without loosing maximum sharpness. Secondly, the amazingly short physical length of the lens reduces the horizontal and vertical travel of the front of the lens in relation to the film plane, thus increasing the sharpness of hand-held shots. Finally, the "solid" glass construction results in an extremely high resistance to damage by shock, a major problem with conventional mirror optics. This combination of environmental resistance, short physical length, and shock resistance assures you of superb performance under the most demanding conditions.

Manufacturer description #2

This lens represents three major advances in catadioptric lens design. it offers the photographer extreme compactness, inherent environmental stability, and superior relative illumination; characteristics that have until now been unattainable in long focal length reflex lens for 35mm photography.

The optical design of the aspherical 600mm solid catadioptric lens is derived from the Cassegrain telescope objective used extensively in astronomical work. The extreme compactness of this lens is attributed to the achievement of a seven-to-one ratio between focal length and barrel length. This compares with a 1.2 to 1 ratio for traditional non-mirror telephoto lenses and about four-to-one for previous reflex lenses. The short physical length of this lens helps to lessen the effect of minor in-camera vibrations such as mirror bounce on image sharpness. Highly acceptable hand-held shots at relatively slow shutter speeds are entirely possible. The photographer can safely violate the rule for normal telephoto lenses that minimum shutter speed should approximate focal length in hand held shooting. (A 600mm lens would require 1/500 second or faster shutter speed.)

Stability has been another major problem in catadioptric lenses. In conventional designs, the optical groups of the lens are separated by large air spaces. Temperature variants often create serious optical alignment anomalies, decreasing sharpness. These lenses are also susceptible to severe mis-alignment caused by minor shocks and vibrations. In the 600mm f8, spherically shaped elements are pieced together to form what is a virtually solid element. As all the optical elements share similar temperature coefficients, the lens is temperature stable even in extreme climates. This near-solid construction also makes the optical alignment highly resistant to damage from impact.

The troublesome "hot spot" present in conventional mirror lenses is almost entirely absent in the Vivitar Series 1 600mm. This " hot spot" results from a difference in illumination between axis and corner of 50% or more. But in the Series 1 solid catadioptric lens fall-off has been reduced to less than 30%, the equivalent of about 1/3 f stop.

As with all mirror telephoto lenses, the Vivitar Series 1 600mm f8 is a fixed aperture lens. Exposure is controlled by camera shutter speed and the use of neutral density filters. In this lens, filters are placed behind the lens in the T-mount, thus allowing the use of smaller Series 1 35.5mm close tolerance VMC filters.

The lens focuses very quickly, since the entire main body of the lens (with primary and secondary mirrors including the afocal double) moves relative to the elements forming the Barlow group which remains at a fixed distance from the film plane. This focusing system requires about one-fourth as much axial travel as would be required if the entire optical system moved as a single unit. The lens can be rotated 360° inside its tripod mounting ring and can be locked in any position. A safety catch holds the lens securely during rotation.

One more unique feature of the Vivitar Series 1 600mm f8 solid catadioptric lens is its development and manufacture entirely by U.S. sources. Working with the Perkin-Elmer Corporation, a world leader in global science and astronomical systems, Vivitar has incorporated the principles of intricate astronomical optics into photographic lenses for the professional and advanced amateur in 35mm photography. The 600mm f8 is the first of a family of solid catadioptric lenses, with 800mm f11 and 1200mm f11 versions scheduled to follow.

The production of Series 1 solid catadioptric lenses, including the 600mm f8 is an exacting, time-consuming process. Optics of this type do not lend themselves to automated, assembly-line manufacture. They are produced individually, each lens being assembled and tested almost as though it were the first one to be built. For this reason, these lenses will be in limited supply.

Filter provision: 35.5mm at the rear of the lens, inside the T-mount. Filters included are Series 1 VMC close tolerance UV haze, K2, 4X ND, and 25A. Screw-in hood, detachable tripod socket, filters, lens case , front and rear lens caps included.

Mounts available to fit Universal Thread, Nikon/Nikkormat, Canon, Minolta, Konica Autoreflex and Olympus OM cameras.

Manufacturer description #3

The Vivitar® 600mm solid catadioptric is the lens that has caused a revolution in telephoto lens photography, especially in the specialized fields of industrial photography, photo journalism and law enforcement use. Carefully crafted precision optics help to make the Vivitar 600 solid CAT the most versatile lens in telephoto photography.

Mirror lenses allow the use of long effective focal lengths without the extreme length and bulk of refractive lenses. But the bane of the mirror lens has been the troublesome "hot-spot"; uneveness of illumination from center to edge of a full f-stop or more.

The optical design of the Vivitar Series 1 600mm f8 solid catadioptric lens virtually eliminates the "hot-spot: The fall-off in illumination from center to edge is one-third of an f-stop or less. In addition to solving the "hot-spot" problem, the Vivitar 600mm CAT is an exceptionally durable and stable lens. Spherical elements are combined to form what is a virtually solid element, thus eliminating the large air spaces and low tolerance to shock and temperature changes found in conventional mirror lenses. In fact, the primary element is 42.7mm thick.

At 100 yards the Vivitar 600mm CAT produces the same image on the 35mm format that a 50mm lens produces at 25 feet. An experienced photographer can hand-hold this compact lens at shutter speeds that would normally be impossible with a 600mm refractor type lens.

The lens is fully compatible with popular 35mm SLR cameras and is also a spectacular optic for 16mm cine cameras accepting "C" mount adapters. The image produced on 16mm film is approximately equivalent to the image of a 2000mm lens on 35mm still film.

Like all mirror lenses the Vivitar 600mm telephoto lens has a fixed aperture. Exposure is controlled with shutter speeds and the use of neutral density filters supplied with the lens.

Vivitar's 600mm solid CAT is no futuristic pipe dream. It is in production and available now at Vivitar dealers.

Manufacturer description #4

News photographers are quite properly suspicious of non-traditional, exotic lenses no matter how tempting the specs may be. But here is a lens that is exotic precisely because of its ability to survive in the company of photojournalists.

The Vivitar Series 1 600mm f8 solid catadioptric lens for 35mm SLR cameras is a different kind of mirror lens. It was developed from the required technology to meet NASA specs for on-board lenses in spacecraft and photographic missions. The 600 CAT lens withstands operating temperatures of 0°-140° Fahrenheit.

In the Vivitar 600mm lens spherically shaped elements are combined to form what is a virtually solid single element. All the optical elements share similar temperature coefficients, so the lens is extremely temperature stable. The glass elements along with the relatively simple focusing mechanism are enclosed in a state-of-the-art lightweight alloy barrel.

The optical design of the lens has virtually eliminated the troublesome "hot-spot" common to mirror lenses; relative illumination varies from center to corner of the format by at most 1/3 f-stop. As with all reflex lenses, the aperture is fixed. Exposure is controlled with shutter speed and the use of neutral density filters supplied with the lens.

Now that you know you can trust the lens to do the job, consider the job it can do. At 100 yards you get the same picture a normal lens would give you at 25 feet. And at 25 feet it will give you a full-frame head and shoulders shot of your subject. That kind of stand-off shooting power comes in handy in a great many newsworthy situations.

This is a lens that can make it possible for you to get the picture when other photographers can't. We think that's the most impressive thing that can be said about any piece of photographic equipment.

The Vivitar Series 1 solid CAT is in production and available at Vivitar dealers. See it now... good news travels fast.

From the Popular Science magazine (March 1975)

... One noteworthy development: the introduction of a line of fine (and expensive) catadioptric telephoto lenses by Vivitar, designed in conjunction with the optical firm of Perkin-Elmer and made in the United States. Who said we couldn't do it?

Vivitar Series I 600mm Solid Catadioptric lens: Amazingly compact for its focal length, this U.S.-made f/8 lens has nine spherical elements in close contact - almost solid glass. Coming (with other cats): June.

From Britannica Book of the Year (1975)

Vivitar introduced a range of compact solid catadioptric (mirror) lenses, the longest focal length being a 1,200-mm. f/11, an 11-element design with an outer diameter of 151 mm. and a total physical length of 172 mm.

From the Camera Afield by Sid Latham (1976)

... Perkin Elmer designed some even smaller. These are true "solid-cat" designs and will be distributed by Ponder & Best under the Vivitar Series I designation. There will be two with f/8 apertures, a 600 and 800mm with fairly close focusing capabilities. They weigh about 3 1/2 pounds, are three inches in length for the 600mm and around 6 1/2 inches for the 800mm. There will also be a 1200mm f/11 at the same length as the 800mm. These are interesting lenses due to recent advances. They have good interior baffling and old-fashioned (all to the good) silver surfacing rather than the widely used aluminizing. In spite of the small size of these lenses it isn't as easy as that to make comparisons.

From the Journal of the Optical Society of America (1976)

A 600 mm f/8 version marketed by Ponder & Best, Inc., with the trade name of Vivitar Series I is about 84mm long and weighs 1.36kg. In the near future two additional objectives will be included in this series; an 800 mm f/11 lenses.

Typical characteristics of mirror (reflex) lenses

  • Catadioptric system consisting of curved mirrors and optical glass;
  • Much shorter, lighter and less expensive designs than conventional super telephoto lenses;
  • Outstanding correction of chromatic aberrations;
  • Since the aperture is fixed, neutral density filters are used to obtain a smaller aperture;
  • Doughnut-shaped out-of-focus highlights.

Notes

  • Independent-brand lenses were made for 35mm film SLR cameras by companies that competed with the camera manufacturers. Some came from factories that made lenses under their own brand names (Angenieux, Kiron, Sigma, Tamron, Tokina). Many others were national and international marketing organizations (Kalimar, Panagor, Rokunar, Soligor, Starblitz) that bought lenses from anonymous manufacturers. One firm — Vivitar — actually designed its own lenses and accessories, which were then subcontracted to manufacturing firms. Still others were private labels, sold only by specific photo specialty shops (Cambron, Quantaray, Spiratone).
  • The actual manufacturer of a Vivitar lens can be identified by the first digits of the serial number: 09 - Cosina, 13 - Schneider-Kreuznach, 19 - Sigma, 22 - Kino Precision Industries, 25 - Ozone Optical, 28 - Komine, 32 - Makina Optical, 33 - Asanuma, 37 - Tokina, 42 - Eugen Bauer, 44 - Perkin Elmer, 47 - Chinon, 51 - Tokyo Trading, 56 - Kyoe Shoji, 61 - Samyang, 6x - Olympus, 75 - Hoya, 77 - Kobori, 81 - Polar, 9x - Cosina. This numbering system, however, was used by Vivitar only between 1969 and 1991 (approx.).
  • This Vivitar lens has s/n 44xxxxx, therefore it was produced by Perkin Elmer.

Lenses with similar focal length

Sorted by manufacturer name

Pentax K mount 3 lenses (2 third-party)
Ricoh XR RIKENON 600mm F/8 Reflex--6 - 62.00m⌀86 1982 
Sigma MF 600mm F/8 Mirror--6 - 62.00m⌀86 1979 
Sigma MF 600mm F/8 Mirror ZEN--7 - 42.00m⌀95 1986 
Canon FD mount 2 lenses (all third-party)
Sigma MF 600mm F/8 Mirror--6 - 62.00m⌀86 1979 
Sigma MF 600mm F/8 Mirror ZEN--7 - 42.00m⌀95 1986 
Contax/Yashica mount 2 lenses (all third-party)
Sigma MF 600mm F/8 Mirror--6 - 62.00m⌀86 1979 
Sigma MF 600mm F/8 Mirror ZEN--7 - 42.00m⌀95 1986 
Konica AR mount 1 lens (third-party)
Sigma MF 600mm F/8 Mirror--6 - 62.00m⌀86 1979 
M42 mount 1 lens (third-party)
Sigma MF 600mm F/8 Mirror--6 - 62.00m⌀86 1979 
Minolta SR mount 2 lenses (all third-party)
Sigma MF 600mm F/8 Mirror--6 - 62.00m⌀86 1979 
Sigma MF 600mm F/8 Mirror ZEN--7 - 42.00m⌀95 1986 
Nikon F mount 2 lenses (all third-party)
Sigma MF 600mm F/8 Mirror--6 - 62.00m⌀86 1979 
Sigma MF 600mm F/8 Mirror ZEN--7 - 42.00m⌀95 1986 
Olympus OM mount 2 lenses (all third-party)
Sigma MF 600mm F/8 Mirror--6 - 62.00m⌀86 1979 
Sigma MF 600mm F/8 Mirror ZEN--7 - 42.00m⌀95 1986 
Interchangeable mount 2 lenses (all third-party)
Soligor C/D 650mm F/8.5 Mirror [T]
aka Osawa 650mm F/8.5 Reflex MC
--7 - 62.00m-- 1981 
MTO-500A 550mm F/8.5 [T]--4 - 34.00m⌀77
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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.

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.

MF

Sorry, no additional information is available.

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 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/8 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.