APS-C
Encyclopedia
Advanced Photo System type-C (APS-C) is an image sensor format
Image sensor format
In digital photography, the image sensor format is the shape and size of the image sensor.The image sensor format of a digital camera determines the angle of view of a particular lens when used with a particular camera...

 approximately equivalent in size to the Advanced Photo System
Advanced Photo System
Advanced Photo System is a film format for still photography first produced in 1996. It was marketed by Eastman Kodak under the brand name Advantix, by FujiFilm under the name Nexia, by AgfaPhoto under the name Futura and by Konica as Centuria.- Design :The film is 24 mm wide, and has three...

 "classic" size negatives. These negatives were 25.1 × 16.7 mm and had an aspect ratio 3:2.

Sensors meeting these approximate dimensions are used in many digital single-lens reflex camera
Digital single-lens reflex camera
Most digital single-lens reflex cameras are digital cameras that use a mechanical mirror system and pentaprism to direct light from the lens to an optical viewfinder on the back of the camera....

s, in addition to a few large-sensored live-preview digital cameras (such as the Sony DSC-R1
Sony Cyber-shot DSC-R1
The Sony Cyber-shot DSC-R1 is a bridge digital camera announced by Sony in 2005 . It featured a 10.3 megapixel APS-C CMOS sensor , a size typically used in DSLRs and rarely used in bridge cameras...

, Sigma DP1
Sigma DP1
The Sigma DP1 is a high-end compact digital camera introduced by the Sigma Corporation. It features a 14-megapixel Foveon X3 sensor , a fixed 16.6 mm F4.0 lens , a 2.5” LCD and a pop-up flash...

 and Leica X1
Leica X1
[File:Leica X1 is a compact fixed-lens, large-sensor digital camera by Leica. The pre-production model was released to reviewers in September 2009....

) and a few digital rangefinders
Rangefinder camera
A rangefinder camera is a camera fitted with a rangefinder: a range-finding focusing mechanism allowing the photographer to measure the subject distance and take photographs that are in sharp focus...

 (e.g. the Epson R-D1
Epson R-D1
The R-D1, announced by Epson in March 2004 and discontinued in 2007, was the first digital rangefinder camera. Manufactured by Cosina, which also builds the current Voigtländer and Zeiss Ikon cameras, the R-D1 and its successor, the Epson R-D1s , use Leica M-mount lenses or earlier Leica screw...

). Such sensors exist in many different variants depending on the manufacturer and camera model. All APS-C variants are considerably smaller than 35 mm standard film which measures 36×24 mm. Sensor sizes range from 20.7×13.8 mm to 28.7×19.1 mm. Each variant results in a slightly different angle of view
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....

 from lenses at the same focal length and overall a much narrower angle of view compared to 35 mm film
135 film
The term 135 was introduced by Kodak in 1934 as a designation for cartridge film wide, specifically for still photography. It quickly grew in popularity, surpassing 120 film by the late 1960s to become the most popular photographic film format...

. This is why each manufacturer offers a range of lenses designed for its format.

Advantages and disadvantages

Compared to the full-frame format, APS-C sensors offer some advantages and disadvantages. Currently, digital SLRs using full-frame sensors are mostly used by professional photographers and serious amateurs. This may be because SLRs with APS-C sensors are considerably cheaper than full-frame cameras. They are also lighter and smaller. Apart from these differences, there are two other important factors. The first is image quality. Theoretically, a larger sensor produces a better image, ie one with more detail and less noise. In practice, the difference may not be obvious and may depend on the use of a high quality lens and on the photographer's skill. The other difference is the crop factor. The smaller APS-C sensor effectively minimizes the field of view by about 1.5, so that a 300mm lens has the same field of view as a 450mm lens on a 35mm. While this crop factor is often called a focal length multiplier, it is important to note that there is no magnification benefit, only a smaller field of view. This means that, although it is possible to use lenses made for the 35mm format on APS-C cameras, most photographers changing from 35mm to APS-C also buy a new set of lenses designed for that format. This is partly to get lenses with wide angle coverage. Also, lenses designed for 35mm may lack sufficient resolution to get the best from smaller formats.

Brand designations

Most DSLR and third party lens manufacturers now make lenses specifically designed for APS-C cameras. The designations by brand include:
  • Canon EF-S
    Canon EF-S lens mount
    The EF-S lens mount is a derivative of the EF lens mount created for a subset of Canon digital single-lens reflex cameras with APS-C sized image sensors. It was released in 2003. Cameras supporting the EF-S mount are backward-compatible with the EF lens mount and, as such, have a flange focal...

  • Nikon DX format
    Nikon DX format
    The Nikon DX format is an alternative name used by Nikon corporation for APS-C image sensor format being approximately 24×16 mm. Its dimensions are about 2/3 those of the 35mm film format . The format was created by Nikon for its digital SLR cameras, many of which are equipped with DX-sized...

  • Pentax
    Pentax
    Pentax is a brand name used by Hoya Corporation for its medical-related products & services and Pentax Ricoh Imaging Company for cameras, sport optics , etc. Hoya purchased and merged with the Japanese optics company on March 31, 2008. Hoya's Pentax imaging business was sold to Ricoh Company, Ltd...

     DA
  • Konica Minolta
    Konica Minolta
    is a Japanese manufacturer of office equipment, medical imaging, graphic imaging, optical devices, and measuring instruments. It is headquartered in the Marunouchi Center Building in Marunouchi, Chiyoda, Tokyo, with a Kansai office in Nishi-ku, Osaka, Osaka Prefecture...

     DT
  • Sony
    Sony
    , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

     DT
  • Sigma DC
  • Samsung NX10
    Samsung NX10
    The Samsung NX10 is a 14.0 effective megapixel APS-C crop CMOS mirrorless interchangeable lens digital camera made by Samsung. It was announced on January 4, 2010...

  • Tamron
    Tamron
    is a Japanese company manufacturing photographic lenses, optical components and commercial/industrial-use optics. Tamron Headquarters is located in Saitama City in the Saitama Prefecture of Japan....

     Di II
  • Tokina
    Tokina
    is a Japanese manufacturer of photographic lenses and CCTV security equipment.-History:Tokina, become a partner of Pentax, division of Hoya Corporation and jointly developed some lenses. These will be available under the Pentax and Schneider Kreuznach D-Xenon and D-Xenogon brands in Pentax K mount...

     DX

Multiplier factors

A crop factor
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...

 (sometimes referred to as a "focal length
Focal length
The focal length of an optical system is a measure of how strongly the system converges or diverges light. For an optical system in air, it is the distance over which initially collimated rays are brought to a focus...

 multiplier", even though the actual focal length is the same) can be used to calculate the 35 mm equivalent focal length
35 mm equivalent focal length
In photography, the 35 mm equivalent focal length is a measure that indicates the angle of view of a particular combination of a camera lens and film or sensor size...

 from the actual focal length. The most common multiplier ratios:
  • 2.0× — Four Thirds system
    Four Thirds System
    The Four Thirds system is a standard created by Olympus and Kodak for digital single-lens reflex camera design and development.The system provides a standard that, with digital cameras and lenses available from multiple manufacturers, allows for the interchange of lenses and bodies from different...

  • 1.7× — Sigma SD14
    Sigma SD14
    The Sigma SD14 is a digital single-lens reflex camera produced by the Sigma Corporation of Japan. It is fitted with a Sigma SA mount which takes Sigma SA lenses....

    , Sigma SD10
    Sigma SD10
    The Sigma SD10 is a digital SLR camera produced by the Sigma Corporation of Japan. It was announced on October 27, 2003 and is an evolution of the previous SD9 model, addressing many of the shortcomings of that camera...

    , Sigma SD9
    Sigma SD9
    The Sigma SD9 is a digital SLR camera produced by the Sigma Corporation of Japan. The camera was launched at the Photo Marketing Association Annual Show on February 18, 2002. It was Sigma's first digital camera, and was the first production camera to use the unique Foveon X3 image sensor, which...

    , Canon EOS DCS 3
    Canon EOS DCS 3
    The Canon EOS DCS 3 was Kodak's first Canon based Digital SLR camera released in July 1995. It uses a modified Canon EOS-1N film camera with a modified Kodak NC2000e digital camera back attached. As a result, it maintained the Canon EF lens mount, and full compatibility with all of Canon's EF...

  • 1.6× — Canon EOS 7D
    Canon EOS 7D
    The Canon EOS 7D is an 18.0 effective megapixel APS-C crop CMOS digital single-lens reflex camera made by Canon. It was announced on September 1, 2009...

    , 500D (T1i/X3)
    Canon EOS 500D
    The Canon EOS 500D is a 15.1 megapixel digital single-lens reflex camera, announced by Canon on 25 March, 2009. It was released in May 2009. It is known as the EOS Kiss X3 in Japan, and as the EOS Rebel T1i in North America...

    , 550D (T2i/X4)
    Canon EOS 550D
    The Canon EOS 550D is an 18.0 megapixel digital single-lens reflex camera, announced by Canon on February 8, 2010. It was made available starting February 24, 2010 and to US dealers starting early March. It is known as the EOS Kiss X4 in Japan, and as the EOS Rebel T2i in North America...

    , 600D (T3i/X5)
    Canon EOS 600D
    The Canon EOS 600D is an 18.0 megapixel digital single-lens reflex camera, released by Canon on February 7, 2011. It is known as the EOS Kiss X5 in Japan and the EOS Rebel T3i in the United States and Canada...

    , 60D
    Canon EOS 60D
    The Canon EOS 60D is a digital single-lens reflex camera from Canon. It is part of the Canon EOS line of cameras and succeeds the EOS 50D. It was publicly announced on August 26, 2010....

    , 50D
    Canon EOS 50D
    The Canon EOS 50D is a 15.1-megapixel digital single-lens reflex camera. It is part of the Canon EOS line of cameras and succeeds the EOS 40D. In turn, it has been succeeded by the EOS 60D....

    , 1000D
    Canon EOS 1000D
    Canon EOS 1000D is a 10.1-megapixel digital single-lens reflex camera announced by Canon on June 10, 2008 and started shipping in mid August of 2008. It is known as the EOS Kiss F in Japan and the EOS Rebel XS in the United States and Canada...

    , 1100D
    Canon EOS 1100D
    Canon EOS 1100D is a 12.2-megapixel digital single-lens reflex camera announced by Canon on February 7, 2011. It is known as the EOS Kiss X50 in Japan and the EOS Rebel T3 in the United States and Canada. The 1100D is an entry-level DSLR that introduces movie mode to Canon's entry level DSLRs and...

    , 40D
    Canon EOS 40D
    The Canon EOS 40D is a 10.1-megapixel semi-professional digital single-lens reflex camera. It was initially announced on August 20, 2007 and was released at the end of that month. It is the successor of the Canon EOS 30D, and is succeeded by the EOS 50D. It can accept EF and EF-S lenses...

    , 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....

    , 30D
    Canon EOS 30D
    The Canon EOS 30D is an 8.2-megapixel semi-professional digital single-lens reflex camera, initially announced on February 21, 2006. It is the successor of the Canon EOS 20D, and is succeeded by the EOS 40D...

    , 450D
    Canon EOS 450D
    The EOS 450D is a 12.2-megapixel digital single-lens reflex camera that is part of the Canon EOS line of cameras. It is the successor to the EOS 400D/Digital Rebel XTi. It was announced on the 23 January 2008 and released in March 2008 and April 2008 in North America...

    , 20Da, 350D
    Canon EOS 350D
    The Canon EOS 350D is an 8.0-megapixel entry-level digital single-lens reflex camera manufactured by Canon. The model was initially announced in February 2005. It uses Compact Flash storage and a Lithium ion battery...

    , 20D
    Canon EOS 20D
    The Canon EOS 20D is an 8.2-megapixel semi-professional digital single-lens reflex camera, initially announced on August 19, 2004 at a recommended retail price of US$1,499. It is the successor of the EOS 10D, and was succeeded by the EOS 30D in August 2006...

    , 300D
    Canon EOS 300D
    The Canon EOS 300D, manufactured by Canon, marketed in North America as the EOS Digital Rebel, and in Japan as the EOS Kiss Digital, is a 6.3-megapixel entry-level digital single-lens reflex camera. It was initially announced on 20 August, 2003 at a price point of $899 without lens, $999 with the...

    , 10D
    Canon EOS 10D
    The Canon EOS 10D is a discontinued 6.3-megapixel semi-professional digital SLR camera, initially announced on February 27, 2003. It replaced the EOS D60, which is also a 6.3-megapixel digital SLR camera. It was succeeded by the EOS 20D in August 2004....

    , D60
    Canon EOS D60
    The Canon EOS D60 is a discontinued 6.3 megapixel digital single lens reflex camera body, announced by Canon on February 22, 2002. It is part of the Canon EOS range, and accepts Canon EF, TS-E and MP-E lenses, but not Canon's later digital-only EF-S lens range.The EOS D60 sits in the prosumer ...

    , D30
    Canon EOS D30
    The Canon EOS D30 is a discontinued 3.1-megapixel professional digital single lens reflex camera body, initially announced by Canon on May 17, 2000. It is part of the Canon EOS line of cameras and uses the EF lens mount. The EOS D30 was Canon's first "home grown" digital SLR...

  • 1.54× — Pentax K20D
    Pentax K20D
    The Pentax K20D and its clone, the Samsung GX-20, were 14.6 megapixel digital single-lens reflex cameras manufactured by Pentax that were announced on January 23, 2008. The K20D was available in the U.S...

    , Pentax K-7
    Pentax K-7
    The Pentax K-7 is a 14.6-megapixel digital single-lens reflex camera, announced on 20 May 2009. This is the first new flagship model released by Pentax since its merger with Hoya Corporation on 31 March 2008.- Features :...

  • 1.53× — Pentax *istD, Pentax *istDs, Pentax *istDs2, Pentax *istDL, Pentax *istDL2, Pentax K100D
    Pentax K100D
    The Pentax K100D and similar Pentax K110D are 6 megapixel digital single-lens reflex cameras, launched in the U.S. on May 22, 2006. The K100D has a maximum resolution of 3008 x 2008, and can also down-sample to 2400 x 1600 and 1536 x 1024...

    , Pentax K100D Super, Pentax K10D
    Pentax K10D
    The Pentax K10D and similar Samsung GX-10 are 10.2 megapixel digital single-lens reflex cameras launched in late 2006. They were developed in a collaboration between Pentax of Japan and Samsung of Korea....

    , Pentax K200D
    Pentax K200D
    The Pentax K200D is a 10.2 megapixel digital single-lens reflex camera, announced on January 24, 2008 along with the higher-end K20D. It was discontinued in December 2008, giving it the distinction of being one of the shortest-lived DSLR cameras....

  • 1.52× — all Nikon
    Nikon
    , also known as just Nikon, is a multinational corporation headquartered in Tokyo, Japan, specializing in optics and imaging. Its products include cameras, binoculars, microscopes, measurement instruments, and the steppers used in the photolithography steps of semiconductor fabrication, of which...

     DSLR cameras except the full-frame D3
    Nikon D3
    The Nikon D3 is a 12.1 megapixel professional grade full frame digital single lens reflex camera announced by the Nikon Corporation on 23 August 2007 along with the Nikon D300 DX format camera. The D3, along with the Nikon D3X, was a flagship model in Nikon's line of DSLRs, superseding the D2Hs...

    , D3s
    Nikon D3S
    The Nikon D3S is a 12.1 megapixel professional-grade full frame digital single-lens reflex camera announced by Nikon Corporation on 14 October 2009. The D3S is the fourth camera in Nikon's line to feature a full frame sensor, following the D3, D700 and D3X. It is also Nikon's first full frame...

    , D3x
    Nikon D3X
    The Nikon D3X is a 24.5 megapixel professional-grade full frame digital single-lens reflex camera announced by the Nikon Corporation on 1 December 2008. The D3X is the third camera in Nikon's line to offer a full frame sensor, following the D3 and D700...

     and D700
    Nikon D700
    The Nikon D700 is a professional grade full-frame digital single-lens reflex camera introduced by the Nikon Corporation in July 2008 and manufactured in Japan. It uses the same 12.1 megapixel "FX" CMOS image sensor as the Nikon D3, and is Nikon's second full-frame digital SLR camera...

    ; all Fuji
    Fujifilm
    is a multinational photography and imaging company headquartered in Tokyo, Japan.Fujifilm's principal activities are the development, production, sale and servicing of color photographic film, digital cameras, photofinishing equipment, color paper, photofinishing chemicals, medical imaging...

    , Sony (except for the full-frame α 850
    Sony α 850
    The α850 was Sony's second full-frame digital SLR, introduced on 27 August 2009. Similar to the DSLR-A900, the camera featured the same 24.6-megapixel full-frame CMOS sensor used in the a900...

    , α 900), newer Pentax DSLRs (k-m
    Pentax K2000
    The Pentax K-m is a 10.2 megapixel digital single-lens reflex camera, announced on September 22, 2008 at the 2008 Photokina trade show along with the DA-L series of lightweight, inexpensive lenses. It was discontinued in November of 2009, being replaced by the more recent Pentax K-x.The K-m is...

    , k-x
    Pentax K-x
    The Pentax K-x is a 12.4 megapixel digital single-lens reflex camera, announced on September 16, 2009. Pentax K-x uses an Exmor, Sony-made sensor . In some cases it even approaches the quality produced by full-frame DSLRs like the Nikon D700 and the Canon 5DMkII, both with larger sensors...

     and later models), and Konica Minolta DSLR cameras.
  • 1.3×Canon EOS-1D Mark IV
    Canon EOS-1D Mark IV
    The EOS-1D Mark IV is a professional 16.1 effective megapixels digital single lens reflex camera camera body produced by Canon. The EOS-1D Mark IV is the successor of the Canon EOS-1D Mark III and was announced on October 20, 2009, just four days after Nikon announced the D3s...

    ††, 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...

    , 1D Mark II
    Canon EOS-1D Mark II
    The EOS 1D Mark II is a professional 8.2 megapixel digital single lens reflex camera camera body produced by Canon. The EOS 1D Mark II is the successor of the EOS 1D.-Features:The EOS 1D Mark II features:* 28.7 × 19.1 mm CMOS sensor...

    (and Mark II N), EOS-1D
    Canon EOS-1D
    The Canon EOS-1D is a 4-megapixel professional digital single-lens reflex camera launched in November 2001. It was Canon's first professional-level digital camera developed and released by themselves, the previous D2000 being a collaborative effort with Kodak. It has a 1.3x crop factor with a CCD...

    ?, Kodak DCS 460
    Kodak DCS
    The Kodak Digital Camera System is a series of digital single-lens reflex cameras and digital camera backs that were released by Kodak in the 1990s and 2000s, and discontinued in 2005. They were all based on existing 35mm film SLRs from Nikon and Canon...

    , DCS 560
    Kodak DCS
    The Kodak Digital Camera System is a series of digital single-lens reflex cameras and digital camera backs that were released by Kodak in the 1990s and 2000s, and discontinued in 2005. They were all based on existing 35mm film SLRs from Nikon and Canon...

    , DCS 660
    Kodak DCS
    The Kodak Digital Camera System is a series of digital single-lens reflex cameras and digital camera backs that were released by Kodak in the 1990s and 2000s, and discontinued in 2005. They were all based on existing 35mm film SLRs from Nikon and Canon...

    , DCS 760
    Kodak DCS
    The Kodak Digital Camera System is a series of digital single-lens reflex cameras and digital camera backs that were released by Kodak in the 1990s and 2000s, and discontinued in 2005. They were all based on existing 35mm film SLRs from Nikon and Canon...

    , Leica M8
    Leica M8
    The Leica M8 is the first digital camera in the rangefinder M series introduced by Leica Camera AG on 14 September 2006. It uses a 10.3-megapixel Kodak KAF-10500 CCD image sensor.As of 15/07/2011, the most recent firmware version is 2.014.-Features:...

    , M8.2

Notes:
Discontinued
††To be discontinued in March 2012.
A 1.3× Focal Length Multiplier is also known as APS-H. Actual multiplier factor is 1.28× for the Canon EOS-1D Mark III and 1.29× for the Canon EOS-1D Mark IV

APS-C lens formats

Canon, Nikon, Sony and Pentax have developed and designed lenses specifically for their cameras with a lens factor (more fully, lens focal length
Focal length
The focal length of an optical system is a measure of how strongly the system converges or diverges light. For an optical system in air, it is the distance over which initially collimated rays are brought to a focus...

 conversion factor) or "crop factor
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...

". APS-C cameras use a smaller area to form the image than traditional 35 mm cameras, and so lenses used on APS-C format cameras have a correspondingly narrower field of view. For example, a 28 mm lens is a wide angle lens on a traditional 35mm camera. But the same lens on an APS-C camera, with a lens factor of 1.6x (relative to a standard full-frame 35mm format camera), has the same angle of view as a 45 mm (28 mm x 1.6 lens factor) lens on a 35 mm camera—i.e. a normal lens. Several third-party lens manufacturers, such as Tamron
Tamron
is a Japanese company manufacturing photographic lenses, optical components and commercial/industrial-use optics. Tamron Headquarters is located in Saitama City in the Saitama Prefecture of Japan....

, Tokina
Tokina
is a Japanese manufacturer of photographic lenses and CCTV security equipment.-History:Tokina, become a partner of Pentax, division of Hoya Corporation and jointly developed some lenses. These will be available under the Pentax and Schneider Kreuznach D-Xenon and D-Xenogon brands in Pentax K mount...

, and Sigma
Sigma Corporation
is a Japanese company founded in 1961, manufacturing cameras, lenses, flashes and other photographic accessories. All Sigma products are produced in the company's own Aizu factory in Bandai, Fukushima, Japan...

, also manufacture a range of lenses optimised for APS-C sensors.

Canon introduced the Canon EF-S line
Canon EF-S lens mount
The EF-S lens mount is a derivative of the EF lens mount created for a subset of Canon digital single-lens reflex cameras with APS-C sized image sensors. It was released in 2003. Cameras supporting the EF-S mount are backward-compatible with the EF lens mount and, as such, have a flange focal...

 of lenses in 2003 alongside the 300D. These lenses place the rear of the lens closer to the camera's sensor (referred to as short back focus). This has several benefits, including lighter lenses and a narrower field of view (which implies “longer” zoom). EF-S lenses are compatible with Canon's APS-C digital SLRs, with the exception of the early Canon D30, Canon D60, and Canon 10D, which predated the introduction of the mounting system. EF-S lenses will not physically mount on Canon's full-frame digital or 35mm film SLRs.

Nikon has their DX format
Nikon DX format
The Nikon DX format is an alternative name used by Nikon corporation for APS-C image sensor format being approximately 24×16 mm. Its dimensions are about 2/3 those of the 35mm film format . The format was created by Nikon for its digital SLR cameras, many of which are equipped with DX-sized...

for their line of APS-C digital cameras. These can be mounted to the full-frame D3, D3x, and D700 models at the cost of fewer megapixels. These lenses generally exhibit vignetting when mounted on Nikon film bodies, but may be usable at longer focal lengths.

Sony has a DT line specifically designed for their APS-C cameras. These lenses can be mounted on any Sony Alpha, but are specifically designed for the a100-a700 series and the earlier Konica Minolta Dynax 5D and 7D. DT lenses can be mounted on an A850 or A900 in "crop" mode, where the frame is cropped and the resolution is halved.

Similarly Pentax produces the DA line for their APS-C cameras. These lenses are available in focal lengths that offer similar field-of-view as lenses previously available for 135 film. The trademark compact design of the DA limited series takes advantage of the smaller APS-C format. All DA lenses can be mounted on Pentax film bodies, albeit with increased vignetting. Only longer focal lengths in the rugged DA* series cover 135 film format fully.

External links

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