Pentax *ist D

APS-C AF digital SLR camera


Production details:
Announced:September 2003
System: Pentax K APS-C (2003)
Maximum format:APS-C
Imaging sensor:23.5 × 15.7mm CCD sensor
Resolution:3008 × 2008 - 6 MP
Crop factor:1.53x
Sensor-shift image stabilization:-
Mount and Flange focal distance:Pentax K [45.5mm]
Model:Electronically controlled
Speeds:30 - 1/4000 + B
Exposure metering:Through-the-lens (TTL), open-aperture
Exposure modes:Programmed Auto
Aperture-priority Auto
Shutter-priority Auto
Physical characteristics:

Manufacturer description #1

PENTAX Corporation has successfully developed a lens-interchangeable digital SLR camera - an innovation that delivers the clarity of 6.1 effective megapixels and satisfies the requirements of various kinds of users. This new advance will be showcased at PMA 2003* (the largest exhibition for photographic equipment in the US), at CeBIT 2003** (the largest exhibition for IT-related products in Europe), and at PHOTOEXPO 2003*** (one of Japan's most comprehensive photographic fairs).

Product outline

  • Product name : PENTAX *ist D
  • Expected launch : June/July 2003

Major features

1) 6.1 effective megapixels

Employing a high-performance CCD with dimensions of 23.5mm x 15.7mm and embracing unique image processing technology, the *ist D achieves impressive 6.1 effective megapixel resolution for the recording of precise, superior quality images.

2) The world's smallest, lightest body*

The architecture of the *ist D has been specially designed to combine the utmost in compact dimensions with surprisingly light weight. Indeed, with dimensions of just 129mm (5.0") x 95mm (3.7") x 60mm (2.3") (width x height x depth) and a weight of just 510g (18 oz.) (not including batteries), the *ist D is the smallest, lightest lens-interchangeable digital SLR camera available.

3) A wide range of compatible PENTAX lenses for flexible shooting

A wide range of compatible PENTAX lenses are available for use with the *ist D, allowing the user to compose satisfying scenes regardless of the type of subject.*

*Compatible lenses: K, KA, KAF, and KAF2 mount lenses; screw mount lenses, 645, and 67 series lenses (adapter required). Some functions may not activate depending on the choice of lens.

4) New pentaprism viewfinder

An optical pentaprism viewfinder was developed especially for the *ist D. This makes viewing easy with an ample 95% field of view and 0.95X magnification. There is also a superimposed display function which assists composition by illuminating the AF points in red.

5) Other features

  • New 16-segment metering system achieves more accurate exposure
  • New 11-point AF sensor (SAFOX VIII) realizes enhanced focusing
  • Fast 1/4000 sec. shutter speed and high-speed flash sync at 1/150 sec.
  • Continuous shooting at approx. 2.7 fps
  • 2-dial system separates aperture and shutter speed settings
  • With individual dials for shutter and aperture selection, Hyper program makes it easy to switch between Shutter-Priority AE and Aperture-Priority AE.
  • Hyper manual let you achieve the proper exposure with simple button operation.
  • Custom function allows functionality to be tuned to satisfy user preferences
  • Noise reduction function activates for long exposures
  • Compatible with MicroDrive and CompactFlash Type I/II
  • Compatible with widely available AA batteries (4 of) or CR-V3 lithium-ion batteries (2 of)
  • PC-based camera control and easy data transmission with USB 1.1 compatibility
  • 1.8 inch, 118,000-pixel LCD monitor for easy, high-precision viewing
  • Convenient playback functions, such as nine imageand 12X magnification-display
  • Choice of JPEG, TIFF and RAW recording formats
  • Comes complete with software compatible with RAW format data
  • Special battery grip (expected to go on sale at the same time as the *ist D)

Manufacturer description #2

Beautiful, High-Resolution Digital Images Assured

A Large-Format CCD with 6.1 Effective Megapixels

The *istD incorporates a large-sized CCD image sensor (23.5mm x 15.7mm) with an impressive 6.1 effective megapixels. As a result, each pixel receives a greater amount of light — that is, information — than smaller counterparts to produce sharp, high-definition images rich in gradation and contrast with minimal noise. Coupled with high-speed image-processing circuitry, it lets you respond quickly and flawlessly to a wide range of shutter opportunities without sacrificing image quality.

The *istD also features a noise reduction function to minimize annoying noise during extended exposures and a low-pass filter to eliminate the interference caused by high-frequency signals.

All combined, the *istD lets you enjoy high-quality digital images with utmost clarity and sharpness.

PENTAX Quality in Every Detail

A Selection of smc PENTAX Lenses to Optimize Visual Expression

One critical factor that determines image quality in SLR photography — both in digital and film formats — is the lens. That's why PENTAX offers a wide array of high-performance smc PENTAX interchangeable lenses — including top-grade FA lenses — to optimize creativity and accommodate a range of applications.

The *istD is designed to be compatible with most of PENTAX's 35mm-format SLR interchangeable lenses.* The FA series, in particular, makes a perfect partner because of its extensive lineup from wide-angle to super-telephoto, as well as its ability to accept the camera's high-precision autofocus mechanism without modifications or limitations.

* In principle, the *istD is compatible with FA J-series lenses and lenses featuring the "A" (automatic diaphragm control) position. Lenses without the "A" position can be used with certain limitations by changing custom function settings.

New-Generation DA Series for Exclusive Use with Digital SLRs

Designed to be extremely compact and lightweight, the new smc PENTAX-DA series elevates the *istD's portability and operability to a new level. The first model, the smc PENTAX-DA 16mm-45mm F4 ED AL (equivalent to 24.5mm-69mm in the 35mm format**), is now available on the market.

** When mounted on the *istD, the focal length of a lens must be multiplied by approximately 1.5 times to determine the focal length equivalent in the 35mm format.

Peerless in Performance and Operability

High-Accuracy 0.95X Viewfinder with Newly Designed Pentaprism

Viewfinder performance is very important in determining image composition and improving the response to shutter opportunities.

The *istD incorporates a newly designed, high-performance glass pentaprism exactly proportioned to match the size of its CCD, instead of adopting a conventional pentaprism used in 35mm-format SLRs.

Offering a bright, high-contrast image with an impressive 95% field of view at 0.95X magnification, its viewfinder assures outstanding accuracy and versatility in composition and picture framing, almost comparable to 35mm-format SLRs.

High-Precision 11-Point Wide-Area AF with Superimposed AF Sensor Point Indicator

The *istD features the sophisticated SAFOX VIII autofocus system, which covers a large part of the image field with 11 AF sensors aligned in the shape of a cross. Even when the subject is positioned off center, the system assures a sharp, crisp focus with exceptional speed and accuracy, allowing you to react swiftly and effortlessly to a wide variety of subjects and situations.

This advanced system also allows you to manually select any one of 11 AF sensor points to match the particular positioning of your subject. The selected sensor point is illuminated with a red LED in the viewfinder when the subject is captured in focus.

Reliable 16-Segment Multi-Pattern Metering to Solve Difficult Lighting

Thanks to its sophisticated 16-segment multi-pattern metering system, the *istD lets you handle complicated lighting conditions with great ease — whether the subject is positioned against backlight or in the shade, or the image is in strong contrast.

Since the *istD's exposure system takes even the subject's distance reading into consideration in determining the optimum exposure level, you can expect well-balanced, beautifully exposed images frame after frame.

The *istD also offers a choice of conventional center-weighted metering and pinpoint spot metering to make you better equipped for specialized applications.

User-Friendly Hyper Program to Couple Automatic Convenience of Programmed Exposure with Creative Manual Control

With the *istD's innovative Hyper Program mode, you can enjoy the best of both worlds — the convenience of automatic exposure control and the creativity of manual operation — with very little effort. It allows you to start taking pictures with the versatile Programmed AE mode, then shift instantly to Shutter-Priority AE or Aperture-Priority AE mode simply by turning the Tv dial in the front or the Av dial on the back to create a specific visual effect. You can always switch back to the initial Programmed AE mode with a single press of the green button.

Responsive Hyper Manual to Harmonize Instant Setting of Optimal Exposure with Creative Freedom of Manual Operation

The moment you press the green button, the *istD's Hyper Manual mode selects the optimal exposure settings for your subject. You're then free to adjust the exposure level using the Tv and Av dials. When the intended exposure is obtained, press the AE lock button to memorize it. This lets you to change the combination of aperture and shutter-speed settings while the exposure is fixed at the memorized level.

Convenient Auto Bracketing to Maximize a Benefit of Digital Photography

A properly exposed image may not always turn out to be your favorite, but digital photography gives you the advantage of recording and erasing images at will. The *istD's auto-bracketing function maximizes this outstanding benefit over conventional film cameras by capturing the subject at three different exposure levels and allowing you to choose the best image on the spot. No more worries about running out of film and letting your once-in-a-lifetime shutter opportunity disappear right in front of you!

Multi-Function Operation for Added Creativity and Convenience

In addition to single-frame advance, the *istD also offers the high-speed consecutive advance mode that lets you record up to six images in succession at a speed of approximately 2.6 frames per second (with the noise reduction function off). It also features such user-friendly functions as multiple exposure, self-timer (with a two- or 12-second delay) and remote shutter release (with an optional remote controller).

Electronic Preview to Confirm the Depth-of-Field

You can easily check the depth-of-field (or in-focus area) in the selected exposure mode before shooting. The preview lever is positioned around the shutter release button for easy access.

Versatile Flash Photography with Built-In and External Flashes

Built into the *istD's pentaprism housing, the high-performance P-TTL auto flash assures accurate exposure on your subject in the dark or at night with its pre-discharge capability. Its red-eye reduction function helps you capture beautiful flash portraits without annoying red eyes.*** When used in combination with the AF360FGZ dedicated auto flash unit, it also offers such advanced functions as contrast-control flash, wireless remote flash, trailing-shutter-curtain sync flash and high-speed sync flash to enhance creativity and convenience.

*** This feature does not eliminate red eyes in all instances.

Super-Rigid Stainless-Steel Chassis with Space-Efficient Body Design

The *istD's chassis is constructed of cold-rolled stainless-steel plates with a thickness of one to 1.2 mm. After thermal treated to increase hardness, these plates are assembled and fixed firmly in place, assuring exceptional unit strength and rigidity without increasing overall weight.

Along with PENTAX's advanced 3D CAD system, this chassis plays an important role in reducing the camera's overall size and weight, as it allows the internal parts to be positioned extremely efficiently with little waste space between them.

Multi-Source Power Supply with AA Battery Compatibility

In addition to two CR-V3 lithium batteries (included), the *istD can be powered by four AA-sized batteries or an optional AC adapter. AA-sized Ni-MH batteries can be recharged for repeated use, while AA-sized alkaline batteries can be easily obtained almost anywhere around the world.

Optional Battery Grip for Extended Photo Sessions and Vertical-Position Shooting

Powered by four AA-sized batteries, the optional D-BG1 battery grip can be mounted to the *istD to considerably extend the overall battery life, letting you capture a greater number of images without battery changes.D-BG1 Its gun-grip design assures a firm, comfortable hold of the camera at any position — not only horizontally, but also vertically — because it is equipped with a separate set of shutter release button, Tv and Av dials, preview lever and AE lock button to facilitate vertical-position shooting.

Versatile and Functional for Advanced Digital Photography

A Choice of Auto, Preset and Manual Settings for White Balance Control

In addition to the convenient automatic white balance control, the *istD allows you to preset white balance for eight different types of lighting conditions. You can also set color temperature manually to optimize image quality for a particular subject.

Independent Three-Step Control over Sharpness, Contrast and Saturation

The *istD gives you the ability to alter sharpness, contrast and saturation independently in three steps, letting you customize the image by increasing contrast, emphasizing highlights and shadows, or by intensifying color density.

Histogram Display for At-a-Glance Exposure Assessment

The brightness distribution of a recorded image can be displayed on the LCD monitor for quick, graphic assessment of the subject's exposure levels. This feature is helpful not only during shooting, but also at playback and editing stages.

22 Custom Functions to Personalize Camera Operation

The *istD lets you preprogram 22 different functions, including program line and exposure setting steps, to meet your preferences. Advanced digital photography is more fun and flawless than ever before with your personalized *istD!

Utmost Quality and Convenience in Image Viewing and Editing

Informative LCD monitor with a Bright, Clear Subject Image

The *istD's 1.8-inch TFT LCD monitor with approximately 118,000 pixels delivers an extra-sharp, high-contrast image to make focusing and picture-framing much easier. Its image display options include single-frame, nine-frame, 12X zoom, slide show, and image rotation.

Effortless Data Transfer and Image Viewing on PC Screen


Images captured by the *istD can be easily transferred to a PC using the included USB cable and monitored on a computer screen using the PENTAX PHOTO Browser software, which is included on the accompanying CD-ROM.

Easy Processing of RAW Data with Fine-Tuning Options


Using the PENTAX PHOTO Laboratory included on the accompanying CD-ROM, you can process RAW data effortlessly into a specific image format with the desired image size. You can also fine-tune the image's white balance, color tone, contrast, saturation and sharpness using this exclusive software.

Similar cameras (4)

APS-C • Auto focus • Digital • Singe-lens reflex • Pentax K mount

Model Shutter Metering Modes Year
Samsung GX-10 E, 1/4000 TTL • OA PASM 2006
Samsung GX-1L E, 1/4000 TTL • OA PASM 2006
Samsung GX-1S E, 1/4000 TTL • OA PASM 2006
Samsung GX-20 E, 1/4000 TTL • OA PASM 2008
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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 in a lens causes a point in the subject to be reproduced as a line in the image. The effect becomes worse towards the corner of the image. Stopping down the lens has very little effect.


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

Curvature of field

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


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

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


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


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

Dynamic range

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

Resolving power

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


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

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

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

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


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


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

Retrofocus design

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


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

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

Rectilinear design

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

Focus shift

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


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

Modulation Transfer Function (MTF)

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

The components of MTF are:

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

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

Veiling glare

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

Anti-reflection coating

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

Benefits of anti-reflection coating:

Circular fisheye

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

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

Diagonal (full-frame) fisheye

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

Extension ring

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

View camera

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

135 cartridge-loaded film

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

120 roll film

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

120 roll film

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

120 roll film

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

220 roll film

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

220 roll film

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

220 roll film

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

Shutter speed ring with "F" setting

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

Catch for disengaging cross-coupling

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

Cross-coupling button

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

M & X sync

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

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

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

X sync

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

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

Unable to follow the link

You are already on the page dedicated to this lens.

Cannot perform comparison

Cannot compare the lens to itself.

Image stabilizer

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

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

Original name

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


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

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

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

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

Angle of view

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

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

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

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


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


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

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

Lens mounts of competing manufacturers (Canon, 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.


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.


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.


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

Lens hood

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

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

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

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


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

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

Lens caps

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