Pentax 645Z

Medium format AF digital SLR camera

Specification

Production details:
Announced:April 2014
System: Pentax 645 (1984)
Format:
Maximum format:Medium format 44x33
Imaging sensor:43.8 × 32.8mm CMOS sensor
Resolution:8256 × 6192 - 51 MP
Sensor-shift image stabilization:-
Mount and Flange focal distance:Pentax 645 [70.87mm]
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:1470g
Dimensions:156x117x123mm

Manufacturer description #1

DENVER, CO, April 9, 2014 – It is not often that a camera can be referred to as a game-changer. One that can provide photographers with the tools that not only enrich their craft but are capable of producing images so distinct they are easily set apart from the competition. Today, Ricoh Imaging Americas Corporation is pleased to announce the game-changing PENTAX 645Z medium-format DSLR, thus altering the landscape of professional photography.

Developed on the multi-award-winning legacy of the PENTAX 645D and the historic PENTAX 645 film cameras, the PENTAX 645Z improves upon one of the most lauded cameras in the company’s 95 year history. Featuring an amazing 51.4 megapixels on a high-performance CMOS image sensor, the PENTAX 645Z assures super-high-resolution images with a stunningly realistic sense of depth combined with vivid colors and rich shadow detail. The resulting images feature a uniquely distinct look and an unmistakable brilliance that clearly differentiate professional photographers to their clients. The thoughtful inclusion of a CMOS image sensor enables live view on a tiltable LCD panel while also making the 645Z the first and only camera in the medium-format category to offer video recording capabilities, resulting in footage that captures amazingly lifelike reproductions with tangible depth and incredible dynamic range.

"Our diverse lineup of DSLRs enables us to offer professional tools like the 645Z at a price point within reach of many photographers," said Jim Malcolm, Executive Vice President, Ricoh Imaging. "Today’s photographers are looking to differentiate their craft and the 645Z offers the perfect option as an exceptional medium-format camera that does not sacrifice in quality or specification, with affordability."

The new PENTAX 645Z has also received several significant enhancements including an improved and highly responsive shooting experience that can capture an incredible three frames per second—a significant benefit when compared to other medium-format cameras featuring CMOS sensors and an equivalent resolution—with a maximum shutter speed of 1/4000 of a second. The 645Z is equipped with an amazing top ISO of 204,800 for images with exceptional quality, even in situations with very low light or pushing for higher shutter speeds in all lighting conditions, providing the photographer with totally new creative options far beyond the scope of existing medium-format photography. Additionally, the 645Z is compatible with the recently introduced FLU Card, providing remote operation of the 645Z including the ability to release the shutter, view a live-view, and browse and download the images recorded on the card using a wireless connection to a smartphone, tablet, computer or any web browser enabled device.

Widening the 645Z’s already diverse applications for shooting is an articulated LCD with a 3.2-inch LCD monitor with approximately 1,037,000 dots, ensuring even the most agile photographer captures waist-level, high and low-angle images with precision and ease. Finally, the PENTAX 645Z features an incredibly sturdy and dependable body with a magnesium alloy frame and a diecast aluminum chassis, complemented by 76 weather-seals for a cold-resistant, weather-resistant and dustproof shooting experience.

In conjunction with the launch of the PENTAX 645Z, Ricoh Imaging is also excited to announce the availability of 13FA 645 lenses to support an even wider variety of optics providing the perfect system that spans numerous shooting scenarios.

Manufacturer description #2

2014.04.15 - RICOH IMAGING COMPANY, LTD. is pleased to announce the launch of the PENTAX 645Z medium-format digital SLR cameras. This new model features a newly designed, large CMOS image sensor with approximately 51.4 effective megapixels to deliver super-high-resolution images, while assuring the outstanding operability and exceptional reliability that can satisfy the exacting demands of professional photographers.

The PENTAX 645Z was developed based on the PENTAX 645D, which was launched in 2010. While retaining the time-proven weather-resistant, dustproof construction, it incorporates a newly developed image sensor and imaging engine to enhance image quality and reliability. It also boasts approximately 51.4 effective megapixels to produce super-high-resolution images with true-to-life sense of depth. It has much-improved basic specifications, such as: burst shooting at approximately three images per second; a tiltable, high-resolution LCD monitor; a state-of-the-art AF system with a live-view function; a high-precision exposure control system; and a more durable, dependable shutter unit. It also provides much faster response to the photographer's commands under all types of shooting conditions. The result is the top level of operability and maneuverability required in demanding professional work. It even features full HD movie recording capability and smartphone accessibility via Wi-Fi transmission to add new possibilities and enhance flexibility in creative photography.

Main Features

1.Super-high-resolution images made possible by approximately 51.4 effective megapixels

The PENTAX 645Z features a high-performance CMOS image sensor, with an imaging area (43.8mm x 32.8mm) approximately 1.7 times larger than that of a 35mm full-size sensor. By combining this sensor with the PRIME III imaging engine -- with its advanced image-processing and noise-reduction capabilities and anti-aliasing filter-less design -- the 645Z makes full use of the imaging power and approximately 51.4 effective megapixels to deliver super-high resolution and exceptional depth rendition. Since the 645Z effectively minimizes annoying noise during high-sensitivity shooting, the photographer can comfortably take pictures even at super-high sensitivities up to ISO 204800. This provides the photographer with totally new creative options beyond the scope of existing medium-format photography.

2.High-speed response to accommodate professional demands

The 645Z continuously records as many as 10 images in the RAW format (or up to 30 images in the JPEG:L・★★★) at a maximum speed of approximately three images per second. It also offers quick-view function, UHS-1 speed class compatibility for high-speed data storage (in the SDR104 bus speed mode; with a compatible SD memory card), and USB3.0-standard data interface for easy transfer of recorded images to a personal computer. Thanks to its high-speed response rivaling that of 35mm-format SLRs, the 645Z assures active, flawless shooting in a wide range of applications demanded by professionals.

3. High-precision AF system

The 645Z incorporates a newly designed SAFOX 11 phase-matching AF module with 27 sensor points (including 25 cross-type sensors). It also detects the light flux of an F2.8 lens to optimize focusing accuracy when using a large-aperture lens. Its wide AF working range of -3EV to +18EV (at ISO 100; at 23oC) to assure pinpoint focus with dimly illuminated subjects, which are difficult to focus accurately with the naked eye. Thanks to the new CMOS image sensor with high-speed data readout, it even provides a live-view function. This allows the photographer to make more minute focus adjustments using the contrast-detection AF mode on the live-view screen, or by magnifying the on-screen image.

4. Tiltable, 3.2-inch LCD monitor with approximately 1,037,000 dots

In addition to its wide-view design, the 645Z's 3.2-inch high-resolution LCD monitor with approximately 1,037,000 dots (in the 3:2 aspect ratio) has a tilt mechanism to adjust the monitor angle, making it easier for the photographer to capture low- and high-angle images. Its front panel is made of tempered glass for extra protection. To optimize visibility during outdoor shooting, it also combines a unique air-gapless construction that eliminates the air space between the LCD layers to reduce the reflection and dispersion of the light, with an AR (Anti-Reflection) coating to minimize reflections on the screen.

5. Full HD movie recording at 1920 x 1080 pixels and 60i frame rate

The 645Z captures beautiful Full HD video clips (1920 x 1080 pixels; 60i/30P frame rate) in the H.264 recording format. Its large image sensor is effective in recording shallow-depth videos with an effectively blurred background. In addition to the built-in stereo microphone, it also provides a stereo mic terminal for external microphone connection and an audio level control function. It even provides interval video recording of 4K-resolution images (3840 x 2160 pixels; in Motion JPEG or AVI video format) to add a new dimension in creative imaging.

6. Solid, dependable body

Both the 645Z's exterior housing and the LCD monitor frame installed on the back are made of sturdy yet lightweight magnesium alloy, while the chassis is made of diecast aluminum to optimize kinematic accuracy and thermal stability against excessive heat. The LCD panels -- one on the camera's top panel, another on its back -- are covered with tempered-glass plates for extra protection against scratches. The camera is also designed to be extremely durable and dependable even in harsh outdoor conditions. It's not only weather-resistant and dustproof with 76 seals applied around the body, but it's also cold-resistant against temperatures as low as -10°C, while its dependable shutter unit has withstood a punishing operation test of more than 100,000 shutter releases.

7. High-precision exposure control supported by PENTAX Real-Time Scene Analysis System

The 645Z features the innovative PENTAX Real-Time Scene Analysis System, which consists of an RGB light-metering sensor with approximately 86,000 pixels and a fine-tuned algorithm. This system not only assures much-improved exposure-control accuracy, but also utilizes the data obtained by the light-metering sensor to further enhance autofocusing accuracy and white-balance adjustment. By accurately assessing the type of scene or subject using the light-metering sensor, the 645Z not only selects the exposure settings that are more consistent with the photographer's creative intentions, but it also makes a clearer distinction between the subject and the background to assure more accurate control of a discharge level in flash photography.

8. Large, bright optical viewfinder

The 645Z features a trapezoid-shaped glass prism, in place of a conventional pentaprism, to assure compact dimensions. Its optical viewfinder provides an approximately 98% field of view to facilitate image composition, while the time-proven Natural-Bright-Matte focusing screen offers a sharp, clear viewfinder image for easier focusing and reduced eye fatigue, even during extended shooting sessions.

9. Smartphone-support functions*

By installing the optional FLUCARD FOR PENTAX 16GB O-FC1 memory card in the 645Z, the user can release the 645Z's shutter, check the live-view image, and browse and download the images recorded on the card using a smartphone.

* This software supports smartphones operating on iOS6® or later and Android™ 4.2 or later.

10. DR II to eliminate dust from the image sensor

The 645Z comes equipped with the highly effective DR (Dust Removal) II mechanism to eliminate annoying dust spots on recorded images. By shifting the UV/IR-cut filter placed in front of the image sensor at supersonic speed using a piezoelectric element, this mechanism effectively and efficiently shakes dust off the image sensor. The 645Z also provides the Dust Alert system, which helps the user detect any dust particles clinging to the image sensor prior to shooting. Thanks to these user-friendly features, the photographer is assured of beautiful, spotless images, even when the lenses are changed in dust-prone outdoor settings.

11. Advanced, professional-grade features

  • When the camera is positioned upside down such as in copying work and bird's-eye-view photography, you can select "Auto Image Rotation mode" that allows you to automatically rotate the image 180 degrees on the camera's LCD monitor or on a computer screen for easier viewing based on the selected position data.
  • The fine square grid on live-view helps you confirm the subject's position in the image field during live-view shooting. You can select grid color from black and white.
  • Lock button disables the camera's control buttons and dial to prevent the accidental shift of settings.

12. Other features

  • Dual SD card slots for memory card flexibility (compatible with SDXC, SDXC UHS-1 speed class in SDR104 bus speed mode)
  • Flexible white balance control, with a newly added Multi-Pattern Auto mode
  • HDR (High Dynamic Range) shooting mode, with RAW-format data filing
  • PENTAX-invented hyper control system for quick, accurate response to the photographer's creative intentions
  • Attachment of copyright credits on recorded images; detection of image tampering using the accompanying software
  • Automatic compensation of lens distortion, lateral chromatic aberration, brightness level at edges, and diffraction
  • Compatibility with Eye-Fi wireless LAN memory cards
  • Compatibility with USB3.0-standard interface accessories, with HDMI™ (type D) terminal
  • Digital Camera Utility 5 software included, to provide enhanced image-processing performance and speed using its newly designed engine
  • Compatibility with IMAGE Transmitter 2 software, for easy transfer of recorded images to PC (optional; available soon)
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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, Leica, Nikon, Pentax, Sony etc.) are always incompatible. In addition to the mechanical and electrical interface variations, the flange focal distance (distance from the mechanical rear end surface of the lens mount to the focal plane) is also different.

Lens construction

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

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

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

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 lens element 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.