Asahi Pentax ME

35mm MF film SLR camera • Discontinued


35mm full frame
Film type:
135 cartridge-loaded film
Pentax K [45.5mm]
Electronically controlled
8 - 1/1000 + B
Exposure metering:
Through-the-lens (TTL), open-aperture
Exposure modes:
Aperture-priority Auto
Physical characteristics:

Manufacturer description #1

There may be more major innovations in this camera than in any 35mm SLR you've ever seen.

The Pentax ME comes from a long tradition of camera innovation.

At Pentax, we practically invented the look of today's 35mm SLR. And we've sold more of them than anyone else in the world.

We were the first to mass-produce 35mm SLRs combining the pentaprism and instant-return mirror. We were the first to use TTL (through-the-lens) light metering. We introduced the first Super-Multi-Coating for 35mm lenses. And we were the first to offer automatic electronic exposure in a 35mm SLR.

At Pentax, we believe our photo engineers have made more major advances in 35mm SLRs than any company in the world.

And we're especially proud of the Pentax ME.

The ME is the smallest, lightest, most compact 35mm SLR in the world. But we didn't achieve this by resorting to plastic materials, like some other leading cameras. The Pentax ME has solid, all-metal cover plates, so it can take a lot of abuse.

Total automation

To free you from as many operational procedures as possible, we've designed into the ME an exposure system so advanced, there is no need to include a conventional shutter speed dial.

Instead, you'll find our unique "shutter control selector." When it's set to "Auto", the ME goes into action as a totally automated, aperture-priority camera. You pick the f/stop. An internal computer picks the precise shutter speed and displays it in the viewfinder.

If you prefer a different shutter speed, simply turn the aperture ring until the speed you desire is displayed. You can do this in less time than it just took you to read about it. And you can do it without taking the camera from your eye.

Once the Pentax ME has decided on an exposure setting for you, you can still override that decision by up to ±2 EVs. So even if you have a special effect in mind, or a peculiar lighting situation to deal with, you still have superb manual control.

Unlike shutter-priority cameras, the aperture-priority ME gives you full control over your depth-of-field. And even with a bellows or other components attached, the ME still functions automatically.

So even though the PentaxNE is fully-automatic, it provides as much manual control and creative flexibility as you're ever likely to need.

The Pentax-Seiko shutter

The Pentax ME features a focal plane shutter jointly invented by Seiko and Pentax. It has received considerable recognition for its accuracy, minimal noise and vibration, and durability. This stepless, automatic shutter helps make the outstanding automatic exposure accuracy of the ME possible.

The panoramic viewfinder

We've taken the concept of TTL metering to its logical conclusion in the ME. The first thing you'll notice when you look into the viewfinder is just how big and bright the image is. The next thing you'll observe is a line of 16 small, solid-state, red LEDs. 14 of these indicate the shutter speed selected by the camera. And two of them indicate whether you're under- or over-exposed.

The light meter. A Pentax first.

Of course, no exposure can be more accurate than the light-sensing capability of the camera. And the light sensors in the ME constitute a major design breakthrough, invented by Pentax in conjunction with Nippon Electric, and first used by Pentax.

They're called Gallium Arsenide Phosphide Photo Diodes (GPDs) and they're a significant improvement over any other light sensor. Even in radical light shifts they react 1,000 times faster than CdS cells. And unlike silicon blue cells, they are immune to infrared radiation. GPDs are extremely stingy with battery power and they can withstand almost any temperature change you'd encounter, without adverse effect. GPDs are definitely the wave of the future. Eventually, you'll probably see them in many SLRs. But we don't mind. We're used to being copied.

Long-lasting power

The two tiny 1.5 volt silver oxide cells will last an unbelievably long time, thanks to the electronic efficiency of the Pentax ME. The camera uses only 3V compared to the 6V required by most other LED readout cameras. Battery life in the ME is expected to last for over 10,000 exposures, even though the batteries power both the shutter and the light meter. You could shoot a 36-exposure roll daily for a year, without battery failure.

When battery power is low, our unique Battery Check Circuit causes the LED visible in the viewfinder to flash on and off, telling you it's time to change batteries. And even when the batteries are dead, you can still keep shooting manually at 1/100 sec. Some other leading 35mm automatics stop operating completely when the batteries die.

Precision lenses

A lot of SLRs have been made smaller lately, but unfortunately, their lenses haven't. Pentax, however, decided to design 19 new ultra-thin, ultra-light M-series lenses for use on the ME. Of course, our regular Pentax lenses also fit the ME. So there are over 40 interchangeable Pentax lenses available to cover any situation, from 2,000mm telephoto to 17mm fisheye. All have Pentax bayonet mounts, which are quickly becoming the standard of the industry. And all have Pentax Super-Multi-Coating, a process which we invented and perfected.

Action shots with the Winder ME

The Pentax ME accepts an automatic winder, the Winder ME, for smooth, quick, automatic film advance. You can attach it in seconds. It fires off exposures at up to 1.5 fps, or if you prefer, one shot at a time.

Dial Data ME back

The back cover of the ME is interchangeable with the compact, easy-to-use Dial Data ME back. With it, you can instantly convert your ME into a data camera, recording the date, or, if you prefer, technical data such as aperture, shutter speed, and frame number.

At Pentax, we've made more major breakthroughs in 35mm SLR design and invention than any other company in the business. In the Pentax ME, we've continued the tradition. Someday, the advances we've incorporated into the ME may be the standard for all SLRs. But for now, they're only available with the original. The Pentax ME.

Manufacturer description #2

TYPE: 35mm full-frame SLR camera with aperture preferred automatic exposure electronic focal-plane shutter and open-aperture center-weighted Through-The-Lens metering

LENS MOUNT: Pentax K bayonet

SHUTTER: Seiko MFC vertical-run metal focal-plane shutter; automatic exposure electronically controlled between B and 1/1000 sec.; manual mechanical speed of 1/100 sec. plus B; provided with shutter button lock and "Cocked" indicator

FLASH SYNCHRONIZATION: X socket on front of camera body, plus X-contact hot/cold accessory shoe; X flash synchronizing at 1/100 sec.

SELF-TIMER: Delays shutter release 4-10 seconds

VIEWFINDER: Silver-coated pentaprism finder; split-image microprism focusing screen; 92% of picture-taking area visible and 0.97x magnification (with 50mm lens at infinity); -0.5 diopter eyepiece. LED dots inside viewfinder indicate automatically selected shutter speeds, plus over and under exposure warning. Correction lens adaptor M, Magnifier M and Refconverter M fit the viewfinder frame

MIRROR AND DIAPHRAGM: Instant-return mirror and automatic diaphragm

FILM WIND AND REWIND: Single-stroke rapid wind lever, plastic-tipped for winding comfort. 135° throw with stand-off angle of 30°. Rapid rewind crank for speedy film rewind

FILM LOADING: New magic-needle quick/sure loading

AUTOMATIC WINDER: ME camera body accepts the new 1.5-frames-per-second automatic film winder, for consecutive or single frame exposure operation

EXPOSURE COUNTER: Automatic reset type

EXPOSURE METER: Open-aperture, center-weighted Through-The-Lens meter, with GPD cells for fast light response, with LED exposure read-out; rapid wind lever and shutter release button acting as meter switch. Exposure range: EV 1-19 (ASA 100, f/1.4). Film speed range: ASA 12-1600. Exposure compensation dial: 1/4x, 1/2x, 1x, 2x, 4x

BATTERY: Two 1.5V silver oxide batteries (G13); LED's double as battery check lamp

BACK COVER: Standard back with memo holder, interchangeable with Dial Data ME for data recording on film

Manufacturer description #3

ME and MX - the world's smallest, lightest, most compact / easy-to-use, full-featured 35mm SLR cameras!

Rugged dependability, innovative technology, ease of use and featured for the professional. All packed into the smallest, lightest SLR cameras in the world!

Advanced Electronic Technology

Solid-state, accurate and reliable electronics are superbly blended with famous Pentax optical quality. IC circuitry and a mini-computer (in the ME) have been integrated in an all new, amazingly compact, camera body.

New Metering Breakthrough

Newly developed GPD's (Gallium Arsenide Phosphorous Diodes) provide exposure accuracy and speed never before attainable. They are 1,000 times faster than conventional CdS cells, and respond instantly to any light change without any 'memory lag'. And, unlike silicon cells, GPD's are insensitive to temperature extremes and infrared.

New Shutter Advances

The fully automatic ME utilizes an improved, smaller version of the Seiko stepless, electronic shutter. The 11 blade, all metal, focal plane shutter is extremely quiet and vibration free.

The new, compact focal plane shutter in the MX has been matched to a new mirror dampening system that virtually eliminates all vibration during an exposure. This new system enables sharp, pictures even in critical close-up photography.

Brilliant Viewfinders

Both the ME and MX have new silvered viewfinders that offer a large, extremely bright image that's easy to focus accurately on. Exposure indications are through LED's which have a new stabilizer and hold circuit that eliminates the common flicker and jumping between the neighboring LED's. The combination split-image and microprism focusing system enables easy, fast pinpoint focusing under any light condition.

A System to Grow With

Auto winders are offered at an easily affordable price for both the ME and the MX. ln addition, a motor drive unit is available for the MX. These will greatly enhance your picture taking capabilities and let both the amateur and the professional concentrate on their picture taking rather than on the operation of the camera. Both the winders and the motor drive unit attach directly to the cameras and are so compact that together with the camera they are equal to most standard cameras in size.

Additionally, there is a whole new line of Ultra-compact lenses and an extensive range of accessories to fulfill every photographer's needs ... and some to even create some new endeavors.

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Cosina C1
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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, 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.


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 lens element 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.