Carl Zeiss C Biogon T* 35mm F/2.8 ZM

Wide-angle prime lens • Film era

C A lens with both compact and classic design.
T* The multi-layer coating is applied to the surface of lens elements. It boosts light transmission, ensures sharp and high contrast images, minimizes ghosting and flares.
ZM The lens is designed for Leica M / Zeiss Ikon 35mm rangefinder cameras.

Zeiss Ikon

35mm MF film rangefinder camera

Announced:September 2004
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:8 - 1/2000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Dimensions:138x72.5x32mm
Weight:395g

Zeiss Ikon SW

35mm MF film viewfinder camera

Announced:August 2006
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:8 - 1/2000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Dimensions:138x78x32mm
Weight:500g

Leica M3

35mm MF film rangefinder camera

Announced:1954
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1 - 1/1000 + B
Exposure metering:No
Dimensions:138x77x33.5mm
Weight:580g

Leica M2

35mm MF film rangefinder camera

Announced:1957
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1 - 1/1000 + B
Exposure metering:No
Dimensions:138x77x33.5mm
Weight:580g

Leica M4

35mm MF film rangefinder camera

Announced:1967
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1 - 1/1000 + B
Exposure metering:No
Dimensions:138x77x33.5mm
Weight:600g

Leica M5

35mm MF film rangefinder camera

Announced:1971
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1/2 - 1/1000 + B
Exposure metering:Through-the-lens (TTL)
Dimensions:155x84x36mm
Weight:685g

Leica M4-2

35mm MF film rangefinder camera

Announced:1978
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1 - 1/1000 + B
Exposure metering:No

Leica M4-P

35mm MF film rangefinder camera

Announced:1981
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1 - 1/1000 + B
Exposure metering:No

Leica M6

35mm MF film rangefinder camera

Announced:1984
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1 - 1/1000 + B
Exposure metering:Through-the-lens (TTL)
Dimensions:138x77x33.5mm
Weight:585g

Leica M6 TTL

35mm MF film rangefinder camera

Announced:1998
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1 - 1/1000 + B
Exposure metering:Through-the-lens (TTL)

Leica M7

35mm MF film rangefinder camera

Announced:February 2002
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:32 - 1/1000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Dimensions:138x79.5x38mm
Weight:610g

Leica MP

35mm MF film rangefinder camera

Announced:March 2003
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1 - 1/1000 + B
Exposure metering:Through-the-lens (TTL)
Dimensions:138x77x38mm
Weight:585g

Leica M-A (typ 127)

35mm MF film rangefinder camera

Announced:September 2014
Mount:Leica M
Format:36 × 24mm
Shutter type:Focal-plane
Shutter model:Mechanical
Speeds:1 - 1/1000 + B
Exposure metering:No
Dimensions:138x77x38mm
Weight:578g

Leica M9

35mm MF digital rangefinder camera

Announced:September 2009
Mount:Leica M
Format:35.8 × 23.9mm
Resolution:5212 × 3472 - 18 MP
Sensor type:CCD
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:32 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:139x80x37mm
Weight:585g

Leica M9-P

35mm MF digital rangefinder camera

Announced:June 2011
Mount:Leica M
Format:35.8 × 23.9mm
Resolution:5212 × 3472 - 18 MP
Sensor type:CCD
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:32 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:139x80x37mm
Weight:585g

Leica M Monochrom (typ 246)

35mm MF digital rangefinder camera

Announced:May 2012
Mount:Leica M
Format:35.8 × 23.9mm
Resolution:5976 × 3992 - 24 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:60 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:138.6x80x42mm
Weight:680g

Leica M (typ 240)

35mm MF digital rangefinder camera

Announced:September 2012
Mount:Leica M
Format:35.8 × 23.9mm
Resolution:5976 × 3992 - 24 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:60 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:138.6x80x42mm
Weight:680g

Leica M-E (typ 220)

35mm MF digital rangefinder camera

Announced:September 2012
Mount:Leica M
Format:35.8 × 23.9mm
Resolution:5212 × 3472 - 18 MP
Sensor type:CCD
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:32 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:139x80x37mm
Weight:585g

Leica M-P (typ 240)

35mm MF digital rangefinder camera

Announced:August 2014
Mount:Leica M
Format:35.8 × 23.9mm
Resolution:5976 × 3992 - 24 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:60 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:138.6x80x42mm
Weight:680g

Leica M Edition 60

35mm MF digital rangefinder camera

Announced:September 2014
Mount:Leica M
Format:35.8 × 23.9mm
Resolution:5976 × 3992 - 24 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:60 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:138.6x80x42mm
Weight:720g

Leica M (typ 262)

35mm MF digital rangefinder camera

Announced:November 2015
Mount:Leica M
Format:35.8 × 23.9mm
Resolution:5976 × 3992 - 24 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:60 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:138.6x80x42mm
Weight:600g

Leica M10

35mm MF digital rangefinder camera

Announced:January 2017
Mount:Leica M
Format:36 × 24mm
Resolution:5976 × 3984 - 24 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:8 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:139x80x38.5mm
Weight:660g

Leica M10-P

35mm MF digital rangefinder camera

Announced:August 2018
Mount:Leica M
Format:36 × 24mm
Resolution:5976 × 3984 - 24 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:8 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:139x80x38.5mm
Weight:675g

Leica M10-D

35mm MF digital rangefinder camera

Announced:October 2018
Mount:Leica M
Format:36 × 24mm
Resolution:5976 × 3984 - 24 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:8 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:139x80x37.9mm
Weight:660g

Leica M (typ 240) E Edition

35mm MF digital rangefinder camera

Announced:June 2019
Mount:Leica M
Format:35.8 × 23.9mm
Resolution:5976 × 3992 - 24 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:32 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:138.6x80x42mm
Weight:680g

Leica M10 Monochrom

35mm MF digital rangefinder camera

Announced:January 2020
Mount:Leica M
Format:36 × 24mm
Resolution:7864 × 5200 - 41 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:16 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:139x80x38.5mm
Weight:675g

Leica M10-R

35mm MF digital rangefinder camera

Announced:July 2020
Mount:Leica M
Format:36 × 24mm
Resolution:7864 × 5200 - 41 MP
Sensor type:CMOS
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:16 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:139x80x38.5mm
Weight:675g

Leica M8

APS-H MF digital rangefinder camera

Announced:September 2006
Mount:Leica M
Format:27 × 18mm - 1.33x
Resolution:3936 × 2630 - 10 MP
Sensor type:CCD
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:32 - 1/8000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:138.6x80.2x36.9mm
Weight:590g

Leica M8.2

APS-H MF digital rangefinder camera

Announced:September 2008
Mount:Leica M
Format:27 × 18mm - 1.33x
Resolution:3936 × 2630 - 10 MP
Sensor type:CCD
Shutter type:Focal-plane
Shutter model:Electronically controlled
Speeds:32 - 1/4000 + B
Exposure metering:Through-the-lens (TTL)
Exposure modes:Aperture-priority Auto
Manual
Image stabilizer:-
Dimensions:138.6x80.2x36.9mm
Weight:600g

Features highlight

Fast
T*
1 AD
Manual
10 blades
MF
Compact
Lightweight

Specification

Production details
Announced:March 2008
Production status:In production
Production type:Mass production
Original name:Carl Zeiss C Biogon 2,8/35 ZM T*
Optical design
Focal length:35mm
Speed:F/2.8
Maximum format:35mm full frame
Mount:Leica M
Flange focal distance:27.8mm
Diagonal angle of view:63.4° (35mm full frame)
49.8° (Leica M APS-H)
Lens construction:7 elements - 5 groups
1 AD
Diaphragm mechanism
Diaphragm type:Manual
Number of blades:10
Focusing
Coupled to the rangefinder:Yes
Closest focusing distance:0.7m (coupled focusing)
Maximum magnification ratio:1:17 at the closest focusing distance
Focusing method:<No information>
Focusing modes:Manual focus only
Manual focus control:Focusing ring
Physical characteristics
Weight:200g
Maximum diameter x Length:⌀52×30mm
Weather sealing:-
Fluorine coating:-
Accessories
Filters:Screw-type 43mm
Lens hood:Bayonet-type 1365-667 (round, vented)

Manufacturer description #1

Carl Zeiss C Biogon T* 2,8/35 ZM

The New Carl Zeiss C Biogon T* 2,8/35 ZM Completes Any Compact Photography Equipment

OBERKOCHEN/Germany, 2008-03-19.

As the latest member of the ZM lens family, the C Biogon T* 2,8/35 ZM lens is the perfect addition to your light, mobile photo equipment. The C Biogon T* 2,8/35 ZM will inspire you with perfect images, even at full aperture. Together with the compact C Biogon T* 4,5/21 ZM, it creates the ideal equipment for a wide range of applications such as documentation and architecture photography.

The “C” in the title indicates another outstanding feature: rather unusual for a lens of this performance class, its moderate speed of 1:2.8 permits an exceptionally compact construction. The symmetrical Biogon construction with 7 lens elements in 5 groups allows for practically distortion-free images.

The ZM lens series from Carl Zeiss is suitable for cameras with M-bayonet. As with the other lenses in this line, the C Biogon T* 2,8/35 ZM features an intuitive operating concept, a robust all-metal frame and a precise, noticeable click in 1/3 aperture stops.

Manufacturer description #2

Be inspired by this compact wide-angle lens with a moderate focal length - the perfect addition to your light, mobile camera equipment.

The ZEISS C Biogon T* 2,8/35 ZM will inspire you with uncompromising image perfection, even at full aperture. The “C” in the title indicates another outstanding feature: Unusual for a lens in this class, its speed of 1 : 2,8 allows for an exceptionally compact construction. With a focal length of 35 mm, it is incredibly versatile and its high performance and compactness make the ZEISS C Biogon T* 2,8/35 ZM an ideal addition to your equipment. Whether you are traveling through impressive landscapes or visiting cities, compiling a news report or attending an event, this little all-rounder always proves a comfortable and reliable companion.

Typical application

landscapes, interiors, buildings, cityscapes, full to mid-body portraits, street, travel

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35mm full frame

43.27 24 36
  • Dimensions: 36 × 24mm
  • Aspect ratio: 3:2
  • Diagonal: 43.27mm

Travellers' choice

Note

Among autofocus lenses designed for 35mm full-frame mirrorless cameras only. Speed of standard and telephoto lenses is taken into account.

One of the best wide-angle prime lenses

According to lens-db.com; among lenses designed for the same maximum format and mount.

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Quality control issues

The manufacturer of this lens does not provide adequate quality control. If you do decide to purchase this lens, do not order it online, but choose the best copy available in the store. In any case, there may also be problems with the build quality, and warranty repairs can take months.

Zeiss Batis series

Professional full-frame autofocus lenses for Sony mirrorless cameras.

Zeiss Loxia series

Compact, full-frame manual focus lenses for Sony mirrorless cameras.

Zeiss Touit series

Autofocus lenses for Sony and Fujifilm APS-C mirrorless cameras.

Zeiss ZM series

Lenses with exceptional workmanship for rangefinder cameras.

Zeiss Otus series

Full-frame manual focus lenses specially designed for modern digital SLR cameras with high-resolution sensors. Deliver uncompromising performance, even at full aperture. Offer the standard of quality otherwise only achieved on medium format systems.

Zeiss Milvus series

Full-frame manual focus lenses specially designed for modern digital SLR cameras with high-resolution sensors. Optimal image performance for all focal lengths.

Zeiss Classic series

Full-frame manual focus lenses developed for ambitious photographers and their wide diversity of applications: macro, landscape, architecture, portrait, journalism, fashion and beauty. Enjoyed an outstanding reputation with photographers all over the world for many years. Characterized by classic appearance and high optical performance. Offer an excellent entry into premium class photography.

Unique Zeiss Look

Zeiss lenses are one-of-a-kind optical masterpieces that are impressive because of their unique Zeiss Look. This is ensured through exceptional optical design combined with selected materials and the highest quality standards.

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.

MF

Sorry, no additional information is available.

Aspherical elements

Aspherical elements (ASPH, XA, XGM) are used in wide-angle lenses for correction of distortion and in large-aperture lenses for correction of spherical aberration, astigmatism and coma, thus ensuring excellent sharpness and contrast even at fully open aperture. The effect of the aspherical element is determined by its position within the optical formula: the more the aspherical element moves away from the aperture stop, the more it influences distortion; close to the aperture stop it can be particularly used to correct spherical aberration. Aspherical element can substitute one or several regular spherical elements to achieve similar or better optical results, which allows to develop more compact and lightweight lenses.

Use of aspherical elements has its downsides: it leads to non-uniform rendering of out-of-focus highlights. This effect usually appears as "onion-like" texture of concentric rings or "wooly-like" texture and is caused by very slight defects in the surface of aspherical element. It is difficult to predict such effect, but usually it occurs when the highlights are small enough and far enough out of focus.

Low dispersion elements

Low dispersion elements (ED, LD, SD, UD etc) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture. This type of glass exhibits low refractive index, low dispersion, and exceptional partial dispersion characteristics compared to standard optical glass. Two lenses made of low dispersion glass offer almost the same performance as one fluorite lens.

Low dispersion elements

Low dispersion elements (ED, LD, SD, UD etc) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture. This type of glass exhibits low refractive index, low dispersion, and exceptional partial dispersion characteristics compared to standard optical glass. Two lenses made of low dispersion glass offer almost the same performance as one fluorite lens.

Canon's Super UD, Nikon's Super ED, Pentax' Super ED, Sigma's FLD ("F" Low Dispersion), Sony' Super ED and Tamron's XLD glasses are the highest level low dispersion glasses available with extremely high light transmission. These optical glasses have a performance equal to fluorite glass.

High-refraction low-dispersion elements

High-refraction low-dispersion elements (HLD) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture.

High Index, High Dispersion elements

High Index, High Dispersion elements (HID) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture.

Anomalous partial dispersion elements

Anomalous partial dispersion elements (AD) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture.

Fluorite elements

Synthetic fluorite elements (FL) minimize chromatic aberrations and ensure excellent sharpness and contrast even at fully open aperture. Compared with optical glass, fluorite lenses have a considerably lower refraction index, low dispersion and extraordinary partial dispersion, and high transmission of infrared and ultraviolet light. They are also significantly lighter than optical glass.

According to Nikon, fluorite easily cracks and is sensitive to temperature changes that can adversely affect focusing by altering the lens' refractive index. To avoid this, Canon, as the manufacturer most widely using fluorite in its telephoto lenses, never uses fluorite in the front and rear lens elements, and the white coating is applied to the lens barrels to reflect light and prevent the lens from overheating.

Short-wavelength refractive elements

High and specialized-dispersion elements (SR) refract light with wavelengths shorter than that of blue to achieve highly precise chromatic aberration compensation. This technology also results in smaller and lighter lenses.

Blue Spectrum Refractive Optics

Organic Blue Spectrum Refractive Optics material (BR Optics) placed between convex and concave elements made from conventional optical glass provides more efficient correction of longitudinal chromatic aberrations in comparison with conventional technology.

Diffraction elements

Diffraction elements (DO, PF) cancel chromatic aberrations at various wavelengths. This technology results in smaller and lighter lenses in comparison with traditional designs with no compromise in image quality.

High refractive index elements

High refractive index elements (HR, HRI, XR etc) minimize field curvature and spherical aberration. High refractive index element can substitute one or several regular elements to achieve similar or better optical results, which allows to develop more compact and lightweight lenses.

Apodization element

Apodization element (APD) is in fact a radial gradient filter. It practically does not change the characteristics of light beam passing through its central part but absorbs the light at the periphery. It sort of softens the edges of the aperture making the transition from foreground to background zone very smooth and results in very attractive, natural looking and silky smooth bokeh.

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 from the lens mount to the film or sensor can also be 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.

Flange focal distance

The flange focal distance (FFD), sometimes called the "flange back", is the distance from the mechanical rear end surface of the lens mount to the focal plane.

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. 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".

Electromagnetic diaphragm control system

Provides highly accurate diaphragm control and stable auto exposure performance during continuous shooting.

Convex protruding front element

The convex front element protrudes from the lens barrel, making it impossible to use filters.

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.

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.