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Sigma SD14

APS-C AF digital SLR camera

Specification

Production details:
Announced:September 2006
System:● Sigma SA APS-C (2002)
Format:
Maximum format:APS-C
Imaging sensor:20.7 × 13.8mm Foveon X3 CMOS sensor
Resolution:2640 × 1760 - 5 MP
Crop factor:1.74x
Sensor-shift image stabilization:-
Mount and Flange focal distance:Sigma SA [44mm]
Shutter:
Type:Focal-plane
Model:Electronically controlled
Speeds:30 - 1/4000 + B
Exposure:
Exposure metering:Through-the-lens (TTL), open-aperture
Exposure modes:Programmed Auto
Aperture-priority Auto
Shutter-priority Auto
Manual
Physical characteristics:
Weight:700g
Dimensions:144x107.3x80.5mm

Manufacturer description

The Sigma Corporation is pleased to announce the launch of the new Sigma SD14 Digital SLR camera.

The new SD14, powered by the 14 megapixel Foveon X3® direct-image-sensor, can reproduce high definition images rich in gradation and impressive three-dimensional detail.

The SD14 Digital SLR camera features four JPEG recording modes, a large and bright pentaprism viewfinder with 98% coverage, a built-in flash with a Guide Number of 11, 5-point AF system, a large 2.5” 150,000 pixel resolution LCD monitor as well as a new user friendly design. The durable shutter mechanism has over 100,000-cycle life and is ideal for the demands of digital photography.

Development

Sigma introduced its first digital SLR camera, the SD9, to the market in October 2002, and has established strong support from a wide range of photographers both amateur and professional alike. The second model, the SD10, released on to the market in November 2003 continued to build on the support of loyal photographers. However, demand for JPEG’s greater convenience in image handling has increased and in order to meet this demand the new SD14, powered by Foveon X3® direct image sensor, now includes JPEG mode with high image quality, high performance and versatility.

Product Summary

14 megapixels Foveon X3® direct image sensor

The Foveon X3® direct image sensor featured in the Sigma SD14 digital SLR can capture all primary RGB colours at each and every pixel arranged in three layers, insuring the capture of full and complete colour. Using three silicon-embedded layers of photo detectors, stacked to take advantage of silicon’s ability to absorb red, green, and blue light at different respective depths, it efficiently reproduces colour more accurately and offers sharper resolution, pixel for pixel, than any conventional image sensor.

Until now, all other image sensors have featured a just single layer of pixels and each pixel captures only one colour of light, which has been filtered through a single colour filter. Since mosaic-based conventional image sensors capture only one-third of the colour, complicated computations are required to interpolate the colours they miss. Interpolation leads to colour errors, colour artifacts and a loss of image detail. Low pass filters must then be used to reduce colour artifacts. The use of low pass filters adversely affect sharpness and resolution of the final image captured.

* Foveon X3 is the registered trademark of Foveon.

In-camera JPEG mode offers added convenience

The SIGMA SD14 incorporates both RAW and JPEG image recording formats enabling photographers to capture the highest possible picture definition and small file sizes. JPEG recording, also built into the SD14, can be used for the following printing sizes;

  • Super High (14.15 million pixels: 4608×3072 pixels) can be used for A3 (297x420mm/11.6"x16.5") or larger prints.
  • High (4.64 million pixels: 2640×1760 pixels) for A4 size (210x297mm/8.2"x11.6") printing.
  • Medium (2.1 million pixels: 1776×1184 pixels) can be used for regular size printing.
  • Low (1.03 million pixels: 1296×864 pixels) can be used for web-page and e-mail transmission.

There is a choice of three JPEG quality settings: Fine, Normal and Basic.

Versatile and easy to use SIGMA Photo Pro 3.0 exclusive software, supplied with the SD14

The SD14 comes complete with SIGMA Photo Pro 3.0 software, a RAW image developer that converts all RAW data quickly and easily. Adjustments can be made in three separate modes. The X3F Mode stores the original settings of the image at the point of capture. In the Auto Adjustment Mode, the software analyses and automatically makes adjustments to the RAW data. The Custom Mode allows the photographer to make individual adjustments (exposure, contrast, shadow, highlight, saturation, sharpness and fill-light for example). The photographer can make subtle or dramatic changes easily and quickly by simply adjusting the slider controls within the software.

The X3F Mode stores the original settings of the image at point of capture. Photographers` personal modifications can be saved to the RAW, X3F file for future use.

SIGMA Photo Pro 3.0 supports 8-bit TIFF, 16-bit TIFF, and JPEG file formats and also outputs images in sRGB, Apple RGB, Adobe RGB and ColourMatch RGB colour spaces. The default setting for output resolution is the same as the resolution selected when capturing the image on the camera (High, Medium, or Low). It is also possible to half, (for sending via e-mails) or double (for high quality enlargements, max. 18.58 million pixels： 5,280 × 3,520 pixels）the resolution when processing the image.

Image Sensor Dust Protector

Most digital SLR cameras are typically vulnerable to dust entering the body especially when the lens is removed for changing. Dust and dirt entering through the lens mount of a digital camera can be seriously detrimental to image quality. The dust protector of the SIGMA SD14 prevents dust from entering and adhering to the image sensor. Even if dust adheres to the dust protector it will not have an adverse influence on image quality as the dust protector is located away from the image sensor and is therefore out of focus.

Large and bright pentaprism viewfinder

The SD14 is equipped with a newly developed pentaprism viewfinder, which has 98％ (vertical and horizontal) coverage with 0.9x magnification, an 18mm eye point and –3 to +1.5 dpt dioptric adjustment.

Large 2.5” LCD monitor

The SD14 camera features a new, large 2.5 inch, 150,000 pixel resolution LCD monitor. The LCD monitor displays 100% of the image, allowing the photographer to easily and accurately confirm the image composition. It features playback options including single frame, thumbnail display (9 images), and three types of magnification (which is achieved by use of the 4-way controller). Shutter speed, aperture and other settings can be seen by pressing the INFO button. The large menu interface makes reviewing images and navigating menu options easy.

Reliable and Durable Shutter

The durable focal plane shutter mechanism has life cycle of over 100,000 exposures. The shutter is ideally suited to the requirements of digital cameras. This new shutter dramatically reduces the amount of dust and dirt from the shutter mechanism. The photographer can enjoy taking pictures without worrying about dirt and dust adhering to the image sensor either from inside or outside the camera.

Fast and precise focusing with 5-point AF

The new auto focus sensor features 5 focusing points (center, left, right, up and down) ensuring consistently fast and precise focusing. The AF metering features a cross type sensor in the center of the screen. Selecting the AF point can be done automatically or manually by photographer.

High speed continuous shooting

The SD14 features a continuous shooting speed of 3 frames per second. Continuous shooting can be accomplished in conjunction with the camera’s predictive auto focus function when photographing fast moving subjects. The camera’s high-speed image processing circuits are capable of handling large data files generated by the high-resolution 14 megapixel sensor. The number of images that can be captured in continuous shooting mode is dependent upon the resolution setting; High - 6 frames, Medium - 12 frames and Low - 24 frames. These figures apply in either RAW or JPEG mode.

Built-in Flash

The Sigma SD14 camera’s built-in flash offers an angle of coverage of 17mm (equivalent to 28mm with 35mm full size) lens with a guide number of 11 (ISO 100). Built-in flash can be synchronized to a shutter speed up to 1/180 sec. This built-in flash enables automatic S-TTL shooting, which allows simple, easy control of advanced photography techniques.

Easy to use multifunction interface

The new layout of control buttons insures quick identification of the desired functions and easy use of the multifunction interface in operating camera settings. Clearly marked buttons make it easy for the photographer to display and adjust the most important settings, namely ISO, resolution, JPEG quality and file type, and white balance on one screen, using one button. The top LCD panel incorporates a backlight, which enables the camera to be easily controlled in low light or dark conditions.

Mirror lock-up mechanism prevents camera shake

The mirror lock-up mechanism raises the mirror thus preventing vibration when the shutter is released. This prevents camera shake, and is especially effective for macro photography, using extremely long telephoto lenses or scientific work. Use of a remote controller (sold separately) or cable release (sold separately) also reduces the possibility of camera shake.

Three types of metering mode

The Sigma SD14 is equipped with three types of metering mode: 8-segment Evaluative Metering, Center Area Metering and Center Weighted Average Metering. This enables the photographer to select the metering mode depending on subject and situation. Exposure compensation function allows the photographer to override the exposure value set by the camera’s exposure meter.

Auto Bracketing function allows the exposure to be adjusted by 1/3 EV increments up to ±3 EV from the exposure automatically set by the camera. In situations where it is difficult to determine proper exposure, the auto bracketing function allows a sequence of pictures to be taken of the same subject at three different exposure levels; Appropriate Exposure, Under Exposure and Over Exposure.

Power Source

The Lithium-ion Battery BP-21 (included with the camera) can shoot approximately 500 images on one full charge. It takes about 120 minutes to fully charge with Battery Charger BC-21 (also included). The optional power grip PG-21 has a vertical shutter release button and can hold two BP-21 batteries, supplying more than enough power for most shoots. The AC Adapter SAC-21 (sold separately) enables the Sigma SD14 to obtain power from the mains supply.

The top LCD panel

The top LCD panel allows the photographer to quickly and accurately confirm information such as resolution setting, metering mode, battery status, and the number of images that can be recorded on the CF card. It also incorporates an orange backlight which enables the camera to be easily controlled in low light or dark conditions.

Optional accessories

The SD14 can be used with over 40 Sigma lenses such as ultra-wide, ultra-telephoto, macro, and fisheye. The EF-500 DG SUPER, EF-500 DG ST, and EM-140 DG flashguns offer fully automatic S-TTL flash dedication. Other accessories include the power grip (PG-21), cable release (CR-21), remote controller (RS-31) and the AC adaptor (SAC-21). These accessories ensure that the SD14 system is both user-friendly and versatile.

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Chromatic aberration

There are two kinds of chromatic aberration: longitudinal and lateral. Longitudinal chromatic aberration is a variation in location of the image plane with changes in wave lengths. It produces the image point surrounded by different colors which result in a blurred image in black-and-white pictures. Lateral chromatic aberration is a variation in image size or magnification with wave length. This aberration does not appear at axial image points but toward the surrounding area, proportional to the distance from the center of the image field. Stopping down the lens has only a limited effect on these aberrations.

Spherical aberration

Spherical aberration is caused because the lens is round and the film or image sensor is flat. Light entering the edge of the lens is more severely refracted than light entering the center of the lens. This results in a blurred image, and also causes flare (non-image forming internal reflections). Stopping down the lens minimizes spherical aberration and flare, but introduces diffraction.

Astigmatism

Astigmatism in a lens causes a point in the subject to be reproduced as a line in the image. The effect becomes worse towards the corner of the image. Stopping down the lens has very little effect.

Coma

Coma in a lens causes a circular shape in the subject to be reproduced as an oval shape in the image. Stopping down the lens has almost no effect.

Curvature of field

Curvature of field is the inability of a lens to produce a flat image of a flat subject. The image is formed instead on a curved surface. If the center of the image is in focus, the edges are out of focus and vice versa. Stopping down the lens has a limited effect.

Distortion

Distortion is the inability of a lens to capture lines as straight across the entire image area. Barrel distortion causes straight lines at the edges of the frame to bow toward the center of the image, producing a barrel shape. Pincushion distortion causes straight lines at the edges of the frame to curve in toward the lens axis. Distortion, whether barrel or pincushion type, is caused by differences in magnification; stopping down the lens has no effect at all.

The term "distortion" is also sometimes used instead of the term "aberration". In this case, other types of optical aberrations may also be meant, not necessarily geometric distortion.

Diffraction

Classically, light is thought of as always traveling in straight lines, but in reality, light waves tend to bend around nearby barriers, spreading out in the process. This phenomenon is known as diffraction and occurs when a light wave passes by a corner or through an opening. Diffraction plays a paramount role in limiting the resolving power of any lens.

Doublet

Doublet is a lens design comprised of two elements grouped together. Sometimes the two elements are cemented together, and other times they are separated by an air gap. Examples of this type of lens include achromatic close-up lenses.

Dynamic range

Dynamic range is the maximum range of tones, from darkest shadows to brightest highlights, that can be produced by a device or perceived in an image. Also called tonal range.

Resolving power

Resolving power is the ability of a lens, photographic emulsion or imaging sensor to distinguish fine detail. Resolving power is expressed in terms of lines per millimeter that are distinctly recorded in the final image.

Vignetting

Vignetting is the darkening of the corners of an image relative to the center of the image. There are three types of vignetting: optical, mechanical, and natural vignetting.

Optical vignetting is caused by the physical dimensions of a multi-element lens. Rear elements are shaded by elements in front of them, which reduces the effective lens opening for off-axis incident light. The result is a gradual decrease of the light intensity towards the image periphery. Optical vignetting is sensitive to the aperture and can be completely cured by stopping down the lens. Two or three stops are usually sufficient.

Mechanical vignetting occurs when light beams are partially blocked by external objects such as thick or stacked filters, secondary lenses, and improper lens hoods.

Natural vignetting (also known as natural illumination falloff) is not due to the blocking of light rays. The falloff is approximated by the "cosine fourth" law of illumination falloff. Wide-angle rangefinder designs are particularly prone to natural vignetting. Stopping down the lens cannot cure it.

Flare

Bright shapes or lack of contrast caused when light is scattered by the surface of the lens or reflected off the interior surfaces of the lens barrel. This is most often seen when the lens is pointed toward the sun or another bright light source. Flare can be minimized by using anti-reflection coatings, light baffles, or a lens hood.

Ghosting

Glowing patches of light that appear in a photograph due to lens flare.

Retrofocus design

Design with negative lens group(s) positioned in front of the diaphragm and positive lens group(s) positioned at the rear of the diaphragm. This provides a short focal length with a long back focus or lens-to-film distance, allowing for movement of the reflex mirror in SLR cameras. Sometimes called an inverted telephoto lens.

Anastigmat

A photographic lens completely corrected for the three main optical aberrations: spherical aberration, coma, and astigmatism.

By the mid-20th century, the vast majority of lenses were close to being anastigmatic, so most manufacturers stopped including this characteristic in lens names and/or descriptions and focused on advertising other features (anti-reflection coating, for example).

Rectilinear design

Design that does not introduce significant distortion, especially ultra-wide angle lenses that preserve straight lines and do not curve them (unlike a fisheye lens, for instance).

Focus shift

A change in the position of the plane of optimal focus, generally due to a change in focal length when using a zoom lens, and in some lenses, with a change in aperture.

Transmittance

The amount of light that passes through a lens without being either absorbed by the glass or being reflected by glass/air surfaces.

Modulation Transfer Function (MTF)

When optical designers attempt to compare the performance of optical systems, a commonly used measure is the modulation transfer function (MTF).

The components of MTF are:

The MTF of a lens is a measurement of its ability to transfer contrast at a particular resolution from the object to the image. In other words, MTF is a way to incorporate resolution and contrast into a single specification.

Knowing the MTF curves of each photographic lens and camera sensor within a system allows a designer to make the appropriate selection when optimizing for a particular resolution.

Veiling glare

Lens flare that causes loss of contrast over part or all of the image.

Anti-reflection coating

When light enters or exits an uncoated lens approximately 5% of the light is reflected back at each lens-air boundary due to the difference in refractive index. This reflected light causes flare and ghosting, which results in deterioration of image quality. To counter this, a vapor-deposited coating that reduces light reflection is applied to the lens surface. Early coatings consisted of a single thin film with the correct refractive index differences to cancel out reflections. Multi-layer coatings, introduced in the early 1970s, are made up of several such films.

Benefits of anti-reflection coating:

Circular fisheye

Produces a 180° angle of view in all directions (horizontal, vertical and diagonal).

The image circle of the lens is inscribed in the image frame.

Diagonal (full-frame) fisheye

Covers the entire image frame. For this reason diagonal fisheye lenses are often called full-frame fisheyes.

Extension ring

Extension rings can be used singly or in combination to vary the reproduction ratio of lenses. They are mounted between the camera body and the lens. As a rule, the effect becomes stronger the shorter the focal length of the lens in use, and the longer the focal length of the extension ring.

View camera

A large-format camera with a ground-glass viewfinder at the image plane for viewing and focusing. The photographer must stick his head under a cloth hood in order to see the image projected on the ground glass. Because of their 4x5-inch (or larger) negatives, these cameras can produce extremely high-quality results. View cameras also usually support movements.

135 cartridge-loaded film

43.27 24 36
  • Introduced: 1934
  • Frame size: 36 × 24mm
  • Aspect ratio: 3:2
  • Diagonal: 43.27mm
  • Area: 864mm2
  • Double perforated
  • 8 perforations per frame

120 roll film

71.22 44 56
  • Introduced: 1901
  • Frame size: 56 × 44mm
  • Aspect ratio: 11:14
  • Diagonal: 71.22mm
  • Area: 2464mm2
  • Unperforated

120 roll film

79.2 56 56
  • Introduced: 1901
  • Frame size: 56 × 56mm
  • Aspect ratio: 1:1
  • Diagonal: 79.2mm
  • Area: 3136mm2
  • Unperforated

120 roll film

89.64 56 70
  • Introduced: 1901
  • Frame size: 70 × 56mm
  • Aspect ratio: 5:4
  • Diagonal: 89.64mm
  • Area: 3920mm2
  • Unperforated

220 roll film

71.22 44 56
  • Introduced: 1965
  • Frame size: 56 × 44mm
  • Aspect ratio: 11:14
  • Diagonal: 71.22mm
  • Area: 2464mm2
  • Unperforated
  • Double the length of 120 roll film

220 roll film

79.2 56 56
  • Introduced: 1965
  • Frame size: 56 × 56mm
  • Aspect ratio: 1:1
  • Diagonal: 79.2mm
  • Area: 3136mm2
  • Unperforated
  • Double the length of 120 roll film

220 roll film

89.64 56 70
  • Introduced: 1965
  • Frame size: 70 × 56mm
  • Aspect ratio: 5:4
  • Diagonal: 89.64mm
  • Area: 3920mm2
  • Unperforated
  • Double the length of 120 roll film

Shutter speed ring with "F" setting

The "F" setting disengages the leaf shutter and is set when using only the focal plane shutter in the camera body.

Catch for disengaging cross-coupling

The shutter and diaphragm settings are cross-coupled so that the diaphragm opens to a corresponding degree when faster shutter speeds are selected. The cross-coupling can be disengaged at the press of a catch.

Cross-coupling button

With the cross-coupling button depressed speed/aperture combinations can be altered without changing the Exposure Value setting.

M & X sync

The shutter is fully synchronized for M- and X-settings so that you can work with flash at all shutter speeds.

In M-sync, the shutter closes the flash-firing circuit slightly before it is fully open to catch the flash at maximum intensity. The M-setting is used for Class M flash bulbs.

In X-sync, the flash takes place when the shutter is fully opened. The X-setting is used for electronic flash.

X sync

The shutter is fully synchronized for X-setting so that you can work with flash at all shutter speeds.

In X-sync, the flash takes place when the shutter is fully opened. The X-setting is used for electronic flash.

Unable to follow the link

You are already on the page dedicated to this lens.

Cannot perform comparison

Cannot compare the lens to itself.

Image stabilizer

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

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

Original name

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

Format

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

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

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

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

Angle of view

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

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

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

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

where:

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

Mount

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

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

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

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

Lens construction

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

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

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

Focal length

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

Speed

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

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

Closest focusing distance

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

Closest working distance

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

Magnification ratio

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

Manual focus override in autofocus mode

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

Manual focus override in autofocus mode

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

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

Manual diaphragm

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

Preset diaphragm

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

Semi-automatic diaphragm

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

Automatic diaphragm

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

Fixed diaphragm

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

Number of blades

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

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

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

Weight

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

Maximum diameter x Length

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

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

Weather sealing

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

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

Fluorine coating

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

Filters

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

Lens hood

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

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

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

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

Teleconverters

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

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

Lens caps

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