Canon T70

35mm MF film SLR camera

Specification

Production details:
Announced:April 1984
System: Canon FD (1971)
Format:
Maximum format:35mm full frame
Film type:135 cartridge-loaded film
Mount and Flange focal distance:Canon FD [42mm]
Shutter:
Type:Focal-plane
Model:Electronically controlled
Speeds:2 - 1/1000 + B
Exposure:
Exposure metering:Through-the-lens (TTL), open-aperture
Exposure modes:Programmed Auto
Shutter-priority Auto
Manual
Physical characteristics:
Weight:530g
Dimensions:151x89.2x48.4mm

Manufacturer description #1

The second T-series camera. The camera kit included an FD 35-70mm f/3.5-4.5 lens or an FD 28-55mm f/3.5-4.5.

The large LCD panel and key-touch buttons had a major impact on 35mm SLR cameras that followed. The T70 features shutter speed-priority TTL AE, TTL multi-program AE, and preset aperture AE. The dual metering system gives a choice of centerweighted averaging metering and partial metering at the center. In 1984, the camera won the Good Design Award (from the Ministry of International Trade and Industry) and the European Camera of the Year Award.

Manufacturer description #2

The T70 is the second in the new T-series of Canon SLRs. Similar in appearance to the T50, with the same off-center pentaprism and sleek, low-profile design, the T70 draws on the latest advances in microprocessor technology to provide a host of sophisticated functions. These include multiple program AE modes, shutter-priority AE, manual override, stopped-down AE and dual metering. A dedicated accessory, the Command Back 70, functions as a combined data back/interval timer. Film loading worries are eliminated by a built-in motor which carries out automatic first frame setting, auto-wind/rewind and continuous shooting.

Multiprogram AE

The T70 meets the need for greater flexibility in programmed photography with three daylight program modes and programmed electronic flash. Each mode is designed to match a specific photographic situation as well as the lens in use. All the programs, however, can be used with any lens.

Standard Program AE

This program is suitable when there is plenty of light and/or when a large maximum aperture lens is used. It selects moderately fast shutter speeds and is ideal for portraiture or snapshots with lenses in the wide-angle to short telephoto range. The viewfinder's P mark flashes as a camera-shake warning (below 1/60 sec).

Wide Program AE

When depth of field is important, switch to this program. The Wide Program increases depth of field by choosing smaller apertures over faster shutter speeds. Especially effective with wide-angle and standard lenses, it gives the photographer more opportunity for creative expression when shooting scenics, group pictures, interiors, etc. The P mark blinks at speeds below 1/30 sec.

Tele Program AE

The Tele Program selects the fastest shutter speed possible under the prevailing lighting conditions. Maximum aperture is maintained up to approx. 1/250 sec. Although effective at all focal lengths, the Tele Program is the ideal program mode for arresting rapid subject motion and minimizing image blur when using telephoto lenses. Camera-shake warning is given at speeds below 1/125 sec.

Shutter-priority AE

For sports and other types of action photography, the T70 offers shutter-priority AE. Shutter speed selection is made by pressing the shift buttons while in the Tv mode. If the light level exceeds the maximum or minimum lens aperture, the T70's special shift function comes into play and the camera switches automatically to a higher or lower speed.

Manual mode

The multiprogrammed T70 is not exclusively automatic. It also provides full manual operation when the need arises. Metering is performed at full aperture and the reading is displayed in the viewfinder. Exposure warnings are also issued whenever necessary.

Time exposure countdown

Time exposures can be made with quartz accuracy. With the shutter speed at "bulb", release the shutter. The frame counter converts to a stopwatch and counts to 30 seconds repeatedly. Dashes mark the 30 sec increments for an accurate record of timed exposures up to 2 minutes long.

Stopped-down AE

Stopped-down AE is another T70 advantage. Canon accessories such as bellows and extension tubes can be attached for close-up and photomacrography uses. Select stopped-down AE by pressing the AE mode selector and either shift button. An aperture mark on the LCD signifies the mode. Now choose an aperture, focus and shoot. The T70 will select the correct shutter speed with computerized accuracy.

Selectable metering

The T70 user can meter the scene with either of two systems: Center-weighted average metering or Selective area metering. This unique feature enables the photographer to choose the metering method that is most appropriate for the subject lighting and lens in use; Greater exposure accuracy is the result. Metering mode selection is made by a simple slide switch. At the heart of the system is a highly sensitive SPC with two independent photosensitive areas that are switched electronically to change the metering pattern.

Center-weighted average metering

This system is suitable for uniformly illuminated scenes without bright highlights. Sensitivity is concentrated on the central picture area where the subject is generally positioned and diminishes toward the edges.

Selective area metering

Strongly backlit subjects tend to come out underexposed when average-metered. Selective area metering solves this problem by limiting metering sensitivity to the central 11% of the image area. This metering pattern offers a more accurate reading with telephoto lenses. An AE lock is available for off-center subjects. Take a reading close up then press the shutter button halfway or press the exposure preview button to lock exposure. The system functions in shutter-priority AE and the program modes.

Full-information viewfinder

Exposure data and warnings are displayed when required to the right ofthe image. The bright laser matte screen's New Split microprism collar is encircled by the selective area metering zone mark.

Built-in motor

Motor driven film advance is an integral feature of the T70. The T70's auto-load function takes the worry out offilm loading. Insert a cartridge and draw the film across to the orange mark. Close the back and the camera fIres off several blank shots until it reaches the fIrst frame position. The film advances automatically upon shutter release. Continuous shooting (at 1.2 frames per sec) is also possible. At film end, a rapid beeping sounds and the LCD flashes. For auto-rewind, slide the release switch and press the rewind button.

Programmed flash

Flash photography is also programmed. A new Speedlite, the 277T, sets the aperture and 1/90 sec sync speed automatically when in the program mode. Press the shutter button gently and the unit fires a low-intensity infrared preflash to measure the distance. The subject reflectivity and the ambient lighting are both computed. The aperture chosen by the flash is indicated in the viewfinder and on the 277T's back panel. lf the subject is too far away, a warning is issued in the viewfinder. A full range of automatic apertures and a more powerful GN expand the flash opportunities in darkness and for fill-in light in daylight. In the F.NO.SET mode, the choice of 8 apertures allows greater control of depth offield and faster recycling time. The 277T's push buttons, LED aperture indicators and forward-tilted design match the T70's futuristic image.

Comprehensive safety functions

Supporting the T70's advanced features and functions is a comprehensive system of monitoring and control devices. User-operable are the back cover latch, rewind button, mode selector and Tv shift locks. The microcircuitry includes such safety features as the shutter-priority AE safety shift function, circuitry protection against reversed battery loading, viewfinder warnings and LCD data including film loading/transport status and battery check. The circuitry scale is several times as great as in the A-1, yet the T70 consumes little energy. Power is provided by two penlight batteries. Contributing to the power-conserving design are the light-load EMAS shutter and low energy consuming time exposure mode. An hourly battery check is made automatically during long exposures.

Canon FD lenses

Being an SLR, the T70 can be used with any lens in the FD range. The system now numbers over 50, from fish-eye to super-telephoto. Each offers superior sharpness, uniform color balance and outstanding handling. Lens changing is rapid and sure thanks to the breech-lock mount. Precision alignment of signals and levers plus elimination ofmount wear are further compelling reasons to choose a Canon lens over other brands.

The T70 lends itself to use with zoom lenses. There are 16 zooms, covering every focal length from 24mm to 600mm. Excellent all-purpose lenses are the New FD 28-55mm and FD 35-70mm, both with a maximum aperture of f/3.5-4.5. The FD 80-200mm f/4 is a popular lens for sports and wildlife photography.

Manufacturer description #3

Type: 35 mm single lens reflex (SLR) camera with electronically controlled automatic exposure (AE) and focal-plane shutter. Wind/rewind fully automatic.

Format: 24 x 36 mm

Exposure modes: Multiprogram AE (Standard program, Tele program, Wide program), shutter-priority AE with safety shift function, manual, stopped-down AE (only for lenses without AE signal pins), program flash AE and electronic flash AE (with Canon Speedlite 277T).

Usable lenses: Canon FD lenses (full aperture metering) and non-FD lenses (stopped-down metering).

Viewfinder: Fixed eye-level pentaprism without condenser. Gives 92% vertical and horizontal coverage of actual picture area and 0.85x magnification at infinity with a standard 50 mm lens

Finder information: Displayed to the right of viewing area. 4 point LED: P lights up steadily when camera is in the program mode and exposure is correct. Flashes at 2 Hz to give camera-shake warning. * lights to indicate AE lock. ↯ lights when the flash is fully charged. M flashes at 4 Hz to indicate manual setting. 2 digital display: Indicates aperture setting in shutter-priority AE and program AE. Indicates shutter speed setting in stopped-down AE. (High shutter speeds are abbreviated so that 1/125-1/350 sec become HL. and 1/500- 1/1000 sec become HH). Display flashes at 8 Hz to indicate over and underexposure. Display flashes at 2 Hz when safety shift function is operating during shutter-priority AE Selective area metering range mark. (In center of screen)

Dioptric adjustment: Built-in eyepiece is adjusted to standard -1 diopter.

Mirror: Quick return type with shock and noise absorber.

Eyepiece cap: Stored in the shoulder pad of the neckstrap.

Light metering system: Through-the-lens (TTL) full aperture metering (for FD lenses), using silicon photocell (SPC). Two selectable weighting patterns, center-weighted average metering and selective area metering. (Selective area metering can only be used with AE lock) (When using lenses or accessories without AE signal pins, only stopped-down metering may be used.)

Meter coupling range: With ISO 100/21°, ASA 100 film and a 50 mm f/1.4 lens: EV 1-19.

Film speed: ISO 12/12° - ISO 1600/33°, ASA 12-ASA 1600 (in 1/3 steps). Displayed on the LCD panel when pressing the ISO button.

Exposure reading: Exposure can be checked by pressing exposure preview button, or by pressing shutter button halfway.

Shutter: Vertical travel electromagnetic attraction focal-plane shutter (EMAS).

Shutter speeds: Automatic: 1/1000 sec-2 sec.

Manual: 12 settings, 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1, 2 sec and Bulb. (X-sync = 1/90 sec.)

Self-timer: Electronically controlled, with a delay of approx 10 sec.

Camera-shake warning: The P mark in the finder flashes at 2 Hz during program AE mode operations for the following shutter speeds: Standard program: 1/60 sec or slower, Tele program: 1/125 sec or slower, Wide program: 1/30 sec or slower.

Film loading and first frame positioning: Automatic. After the film has been positioned and the back cover closed, the film is automatically advanced to the 1st usable frame and then automatically stopped. Three blank frames are advanced. The frame counter display then reads "1".

Film wind: Automatic using built-in motor, enabling continuous shooting. Confirmation by floating bar marks on LCD panel. When the end of the film is reached, the film-load indicator and the frame counter number on the LCD panel start blinking. A beeping sound is also emitted.

Film rewind: Automatic using built-in motor. Automatic stop after film has been rewound into the cartridge. Rewind completion is indicated on LCD panel.

Frame counter: Shown on the LCD panel. Additive type with numbers 1-39, counts down during film rewind.

Back cover: Removable, with memo holder. Opened sliding latch with safety lock.

Flash contact: Coupled directly to the camera by means of the X-contact on the accessory shoe.

Automatic flash: Program flash AE: With the Speedlight 277T. After sending out an infrared pre-flash to judge the distance and the reflectivity of the subject, the 277T sets the aperture and 1/90 sec shutter speed automatically. When out of shooting distance range (too far away), a warning is given, indicated by the aperture value flashing in the viewfinder. Electronic flash AE: With the 277T in "F.NO. SET" mode, or with other Canon Speedlites, shutter speed is set automatically to X-sync and aperture to the f/stop that has been sey on the flash.

Power source: Main power source: Two AA size (3V) batteries. Alkaline batteries are standard but carbon-zinc and Ni-Cd batteries may also be used. Memory back-up: Built-in lithium battery (BR-1225 or CR-1220), battery life is approx. 5 years.

Power switch: The power is turned OFF by setting the main switch to "LOCK".

Battery check: By pressing the battery check (BC) button. Three energy levels are shown by bar marks on the LCD.

Remote control: Possible. With three-terminal contact for remote control. Remote Switch 60 T3 is required.

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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.

Unable to follow the link

You are already on the page dedicated to this lens.

Cannot perform comparison

Cannot compare the lens to itself.

Image stabilizer

A technology used for reducing or even eliminating the effects of camera shake. Gyro sensors inside the lens detect camera shake and pass the data to a microcomputer. Then an image stabilization group of elements controlled by the microcomputer moves inside the lens and compensates camera shake in order to keep the image static on the imaging sensor or film.

The technology allows to increase the shutter speed by several stops and shoot handheld in such lighting conditions and at such focal lengths where without image stabilizer you have to use tripod, decrease the shutter speed and/or increase the ISO setting which can lead to blurry and noisy images.

Original name

Lens name as indicated on the lens barrel (usually on the front ring). With lenses from film era, may vary slightly from batch to batch.

Format

Format refers to the shape and size of film or image sensor.

35mm is the common name of the 36x24mm film format or image sensor format. It has an aspect ratio of 3:2, and a diagonal measurement of approximately 43mm. The name originates with the total width of the 135 film which was the primary medium of the format prior to the invention of the full frame digital SLR. Historically the 35mm format was sometimes called small format to distinguish it from the medium and large formats.

APS-C is an image sensor format approximately equivalent in size to the film negatives of 25.1x16.7mm with an aspect ratio of 3:2.

Medium format is a film format or image sensor format larger than 36x24mm (35mm) but smaller than 4x5in (large format).

Angle of view

Angle of view describes the angular extent of a given scene that is imaged by a camera. It is used interchangeably with the more general term field of view.

As the focal length changes, the angle of view also changes. The shorter the focal length (eg 18mm), the wider the angle of view. Conversely, the longer the focal length (eg 55mm), the smaller the angle of view.

A camera's angle of view depends not only on the lens, but also on the sensor. Imaging sensors are sometimes smaller than 35mm film frame, and this causes the lens to have a narrower angle of view than with 35mm film, by a certain factor for each sensor (called the crop factor).

This website does not use the angles of view provided by lens manufacturers, but calculates them automatically by the following formula: 114.6 * arctan (21.622 / CF * FL),

where:

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

Mount

A lens mount is an interface — mechanical and often also electrical — between a camera body and a lens.

A lens mount may be a screw-threaded type, a bayonet-type, or a breech-lock type. Modern camera lens mounts are of the bayonet type, because the bayonet mechanism precisely aligns mechanical and electrical features between lens and body, unlike screw-threaded mounts.

Lens mounts of competing manufacturers (Canon, Nikon, Pentax, Sony etc.) are always incompatible. In addition to the mechanical and electrical interface variations, the flange focal distance can also be different.

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

Lens construction

Lens construction – a specific arrangement of elements and groups that make up the optical design, including type and size of elements, type of used materials etc.

Element - an individual piece of glass which makes up one component of a photographic lens. Photographic lenses are nearly always built up of multiple such elements.

Group – a cemented together pieces of glass which form a single unit or an individual piece of glass. The advantage is that there is no glass-air surfaces between cemented together pieces of glass, which reduces reflections.

Focal length

The focal length is the factor that determines the size of the image reproduced on the focal plane, picture angle which covers the area of the subject to be photographed, depth of field, etc.

Speed

The largest opening or stop at which a lens can be used is referred to as the speed of the lens. The larger the maximum aperture is, the faster the lens is considered to be. Lenses that offer a large maximum aperture are commonly referred to as fast lenses, and lenses with smaller maximum aperture are regarded as slow.

In low-light situations, having a wider maximum aperture means that you can shoot at a faster shutter speed or work at a lower ISO, or both.

Closest focusing distance

The minimum distance from the focal plane (film or sensor) to the subject where the lens is still able to focus.

Closest working distance

The distance from the front edge of the lens to the subject at the maximum magnification.

Magnification ratio

Determines how large the subject will appear in the final image. Magnification is expressed as a ratio. For example, a magnification ratio of 1:1 means that the image of the subject formed on the film or sensor will be the same size as the subject in real life. For this reason, a 1:1 ratio is often called "life-size".

Manual focus override in autofocus mode

Allows to perform final focusing manually after the camera has locked the focus automatically. Note that you don't have to switch camera and/or lens to manual focus mode.

Manual focus override in autofocus mode

Allows to perform final focusing manually after the camera has locked the focus automatically. Note that you don't have to switch camera and/or lens to manual focus mode.

Electronic manual focus override is performed in the following way: half-press the shutter button, wait until the camera has finished the autofocusing and then focus manually without releasing the shutter button using the focusing ring.

Manual diaphragm

The diaphragm must be stopped down manually by rotating the detent aperture ring.

Preset diaphragm

The lens has two rings, one is for pre-setting, while the other is for normal diaphragm adjustment. The first ring must be set at the desired aperture, the second ring then should be fully opened for focusing, and turned back for stop down to the pre-set value.

Semi-automatic diaphragm

The lens features spring mechanism in the diaphragm, triggered by the shutter release, which stops down the diaphragm to the pre-set value. The spring needs to be reset manually after each exposure to re-open diaphragm to its maximum value.

Automatic diaphragm

The camera automatically closes the diaphragm down during the shutter operation. On completion of the exposure, the diaphragm re-opens to its maximum value.

Fixed diaphragm

The aperture setting is fixed at F/ on this lens, and cannot be adjusted.

Number of blades

As a general rule, the more blades that are used to create the aperture opening in the lens, the rounder the out-of-focus highlights will be.

Some lenses are designed with curved diaphragm blades, so the roundness of the aperture comes not from the number of blades, but from their shape. However, the fewer blades the diaphragm has, the more difficult it is to form a circle, regardless of rounded edges.

At maximum aperture, the opening will be circular regardless of the number of blades.

Weight

Excluding case or pouch, caps and other detachable accessories (lens hood, close-up adapter, tripod adapter etc.).

Maximum diameter x Length

Excluding case or pouch, caps and other detachable accessories (lens hood, close-up adapter, tripod adapter etc.).

For lenses with collapsible design, the length is indicated for the working (retracted) state.

Weather sealing

A rubber material which is inserted in between each externally exposed part (manual focus and zoom rings, buttons, switch panels etc.) to ensure it is properly sealed against dust and moisture.

Lenses that accept front mounted filters typically do not have gaskets behind the filter mount. It is recommended to use a filter for complete weather resistance when desired.

Fluorine coating

Helps keep lenses clean by reducing the possibility of dust and dirt adhering to the lens and by facilitating cleaning should the need arise. Applied to the outer surface of the front and/or rear lens elements over multi-coatings.

Filters

Lens filters are accessories that can protect lenses from dirt and damage, enhance colors, minimize glare and reflections, and add creative effects to images.

Lens hood

A lens hood or lens shade is a device used on the end of a lens to block the sun or other light source in order to prevent glare and lens flare. Flare occurs when stray light strikes the front element of a lens and then bounces around within the lens. This stray light often comes from very bright light sources, such as the sun, bright studio lights, or a bright white background.

The geometry of the lens hood can vary from a plain cylindrical or conical section to a more complex shape, sometimes called a petal, tulip, or flower hood. This allows the lens hood to block stray light with the higher portions of the lens hood, while allowing more light into the corners of the image through the lowered portions of the hood.

Lens hoods are more prominent in long focus lenses because they have a smaller viewing angle than that of wide-angle lenses. For wide angle lenses, the length of the hood cannot be as long as those for telephoto lenses, as a longer hood would enter the wider field of view of the lens.

Lens hoods are often designed to fit onto the matching lens facing either forward, for normal use, or backwards, so that the hood may be stored with the lens without occupying much additional space. In addition, lens hoods can offer some degree of physical protection for the lens due to the hood extending farther than the lens itself.

Teleconverters

Teleconverters increase the effective focal length of lenses. They also usually maintain the closest focusing distance of lenses, thus increasing the magnification significantly. A lens combined with a teleconverter is normally smaller, lighter and cheaper than a "direct" telephoto lens of the same focal length and speed.

Teleconverters are a convenient way of enhancing telephoto capability, but it comes at a cost − reduced maximum aperture. Also, since teleconverters magnify every detail in the image, they logically also magnify residual aberrations of the lens.

Lens caps

Scratched lens surfaces can spoil the definition and contrast of even the finest lenses. Lens covers are the best and most inexpensive protection available against dust, moisture and abrasion. Safeguard lens elements - both front and rear - whenever the lens is not in use.