Canon EF 300mm lens
Encyclopedia
The EF 300mm lens refers to five telephoto prime
Prime lens
In film and photography, a prime lens is either a photographic lens whose focal length is fixed, as opposed to a zoom lens, or it is the primary lens in a combination lens system....

 lenses
Photographic lens
A camera lens is an optical lens or assembly of lenses used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically.While in principle a simple convex lens will suffice, in...

 made by Canon. The lenses have an EF
Canon EF lens mount
Introduced in 1987, the EF lens mount is the standard lens mount on the Canon EOS family of SLR film and digital cameras. EF stands for "Electro-Focus": automatic focusing on EF lenses is handled by a dedicated electric motor built into the lens...

 type mount which fits the Canon EOS
Canon EOS
The Canon EOS autofocus 35 mm film and digital SLR camera system was introduced in 1987 with the Canon EOS 650 and is still in production as Canon's current DSLR system...

 line of cameras.

When used on a digital
Digital photography
Digital photography is a form of photography that uses an array of light sensitive sensors to capture the image focused by the lens, as opposed to an exposure on light sensitive film...

 EOS body with a field of view
Crop factor
In digital photography, a crop factor is related to the ratio of the dimensions of a camera's imaging area compared to a reference format; most often, this term is applied to digital cameras, relative to 35 mm film format as a reference. In the case of digital cameras, the imaging device would be a...

 compensation factor of 1.3x, such as the Canon EOS-1D Mark III
Canon EOS-1D Mark III
The EOS 1D Mark III is a professional 10.1 megapixel digital single lens reflex camera camera body produced by Canon. The EOS 1D Mark III was announced on February 21, 2007 and is the successor of the Canon EOS-1D Mark II N and was first released in May 2007...

, it provides a narrow field of view, equivalent to a 390 mm lens mounted on a 35mm
35 mm film
35 mm film is the film gauge most commonly used for chemical still photography and motion pictures. The name of the gauge refers to the width of the photographic film, which consists of strips 35 millimeters in width...

 frame body. With a 1.6x body such as the Canon EOS 400D
Canon EOS 400D
The EOS 400D, called Digital Rebel XTi in North America and EOS Kiss Digital X in Japan, is a mid-range digital single-lens reflex camera introduced by Canon August 24, 2006....

, it provides a narrower field of view, equivalent to a 480 mm lens mounted on a 35mm frame body.

This lens is most commonly used by sports and wildlife photographers, but is short enough to be use for extreme close-up portrait
Portrait
thumb|250px|right|Portrait of [[Thomas Jefferson]] by [[Rembrandt Peale]], 1805. [[New-York Historical Society]].A portrait is a painting, photograph, sculpture, or other artistic representation of a person, in which the face and its expression is predominant. The intent is to display the likeness,...

s. Because of its rather high native magnification, it can be used for some macro type photography.

Technical information

The EF 300mm is a L series
Canon l lens
An L lens is a line of SLR photography lenses made by Canon.L lenses are Canon's top-of-the-line lenses. The "L" officially stands for "Luxury", a reference to the lenses' high price and proclaimed build quality. The use of "ASPH" was common to notate aspherical elements throughout Canon's and...

 lens. This lens is constructed with a metal body and mount, and with plastic extremities and switches. Features of this lens are: a wide rubber focus ring that is damped
Damping
In physics, damping is any effect that tends to reduce the amplitude of oscillations in an oscillatory system, particularly the harmonic oscillator.In mechanics, friction is one such damping effect...

, a distance window, the ability to limit the focus range, and an image stabilizer
Image stabilization
Image stabilization is a family of techniques used to reduce blurring associated with the motion of a camera during exposure. Specifically, it compensates for pan and tilt of a camera or other imaging device. It is used in image-stabilized binoculars, still and video cameras, and astronomical...

 (on the IS versions). The maximum aperture
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...

 of 2.8 or 4 gives this lens the ability to create shallow depth of field
Depth of field
In optics, particularly as it relates to film and photography, depth of field is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image...

 effects, while an eight-blade diaphragm produces smooth background blur. The optical construction of this lens contains 15 lens elements, including two UD (Ultra low dispersion
Dispersion (optics)
In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.Media having such a property are termed dispersive media...

) lens elements. This lens uses an inner focusing
Focus (optics)
In geometrical optics, a focus, also called an image point, is the point where light rays originating from a point on the object converge. Although the focus is conceptually a point, physically the focus has a spatial extent, called the blur circle. This non-ideal focusing may be caused by...

 system, powered by a ring type USM
Ultrasonic motor
An ultrasonic motor is a type of electric motor powered by the ultrasonic vibration of a component, the stator, placedagainst another component, the rotor or slider depending on the scheme of operation...

 motor. The front of the lens does not rotate nor extend when focusing. This lens is compatible with the Canon Extender EF
Canon Extender EF
The Extender EF lenses are a group of teleconverter lenses made by Canon. These lenses are used between any compatible EF type lens and any of the Canon EOS line of cameras. When used with a compatible lens, such as the Canon EF 500mm 4L IS USM, they will multiply the focal length of the lens by a...

 teleconverters.

Versions

Attribute 2.8 USM 2.8 IS USM 2.8 IS II USM 4 USM 4 IS USM
Image
Image stabilizer
 No
 Yes
 Yes
 No
 Yes
Ring USM
 Yes
L-series
 Yes
Diffractive Optics
 No
Ultra-low dispersion glass element
 Yes
Macro
Macro photography
Macrophotography is close-up photography, usually of very small subjects. Classically a macrophotograph is one in which the size of the subject on the negative is greater than life size. However in modern use it refers to a finished photograph of a subject at greater than life size...

 Yes
Short back focus
 No
Maximum aperture
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...

2.8 4
Minimum aperture
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...

32
Weight 2.855 kg 2.550 kg 2.400 kg 1.165 kg 1.190 kg
Max. Diameter x Length 12.8 cm x 25.2 cm 12.8 cm x 24.8 cm 9.0 cm x 22.1 cm
Filter diameter 48 mm drop-in 52 mm drop-in 77 mm
Horizontal viewing angle
Angle of view
In photography, 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....

6° 50'
Vertical viewing angle
Angle of view
In photography, 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....

4° 35'
Diagonal viewing angle
Angle of view
In photography, 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....

;
8° 15'
Groups/elements 8/10 13/17 12/16 7/8 11/15
# of diaphragm
Diaphragm (optics)
In optics, a diaphragm is a thin opaque structure with an opening at its center. The role of the diaphragm is to stop the passage of light, except for the light passing through the aperture...

 blades
8 9 8
Closest focusing distance 3 m 2.5 m 2 m 2.5 m 1.5 m
Release date November 1987 July 1999 September 2010 December 1991 March 1997
MSRP
Suggested retail price
The manufacturer's suggested retail price , list price or recommended retail price of a product is the price which the manufacturer recommends that the retailer sell the product. The intention was to help to standardise prices among locations...

 $
United States dollar
The United States dollar , also referred to as the American dollar, is the official currency of the United States of America. It is divided into 100 smaller units called cents or pennies....

$3,499 $4,879 $7,299 $1,199 $1,399
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