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Sigma Lenses for Digital SLR Cameras

a photo.net guide by Hannah Thiem, November 2008 (updated September 2015)

Since 1961 Sigma has been dedicated to the science and the art of photography. Sigma is mainly known as a third-party lens manufacturer, producing lenses in mounts compatible with the major brands: Canon, Nikon, Pentax, Sony, Olympus. They offer high-quality glass in many of the popular focal lengths which, in many cases, are at more affordable prices than the specific manufacturer’s offerings. A Sigma lens can be an intelligent choice for owners of small-sensor cameras such as the Canon Digital Rebel T5i or EOS 70D and the Nikon D7200, the Pentax K3-II and the Sony a77. The lens offerings from Sigma for full-frame sensor cameras are also good choices, but as always it’s best to test before you buy and of course we recommend asking your peers about their experiences which can be easily done in our forums. In our experience your peers are by far the best sources of information you can obtain because they are using the equipment as you would likely use it i real world hands on experiences and not in a laboratory. By all accounts Sigma produces quality products for photographers and has a firm foothold in being among the best in the business.

This article covers every current Sigma product.

If you are new to photography, you might want to read Building a Digital SLR System, or Factors to Consider when Choosing a Digital SLR Camera.

For the complete catalog of Sigma products and Sigma-related articles, forum threads, etc, visit the SigmaCameras & Equipment Guide.


  • EX – EX Lens. Denotes superior build and optical quality (similar to Canon’s “L” and Nikon’s “G” specification).
  • DG – For full-frame digital and 35mm film cameras. The image circle on these lenses are suitable for full-frame digital and 35mm film cameras. Sigma has concentrated on the correction of distortion and aberrations.
  • DC – For cropped sensor digital cameras including APS-C and Four Thirds. The image circle on these lenses match the smaller size of image sensor on small-frame sensor cameras (DX-format on Nikon, EF-S on Canon).
  • HSM – Hyper-Sonic Motor. HSM lenses use a motor driven by ultrasonic waves to provide quiet fast AF, Sigma’s version of Canon’s in-lens ultrasonic motor. HSM makes autofocus faster and facilitates simultaneous use of manual and autofocus.
  • DF – Dual Focus. The DF system disengages the linkage between the internal focusing mechanism and outer focusing ring when the focusing ring is moved to the AF position. This system provides easy and precise handling of the lens, since the focusing ring does not rotate during autofocusing. The wide focusing ring also enables easy and accurate manual focusing.
  • OS – Optical Stabilizer Function. Using a built-in mechanism, camera shake is compensated. When photographing hand held, the OS function allows for more stable shots.
  • APOApochromatic Lens. APO lenses minimize color aberration. The Sigma APO lenses are made using special low-dispersion glass, which helps to compensate for color aberration, allowing for sharper images.
  • IF – Internal Focus. Lenses with this designation move the inner lens group or groups without changing the lens’ physical length to ensure stability in focusing.
  • CONVAPO Teleconverter EX. Lenses with this designation can be used with the Sigma APO Teleconverter EX. Using it will increase the focal length and it will interface with the camera’s auto exposure function.
  • RF – Rear Focus. Lenses with this designation are equipped with a system that moves the rear lens group for highspeed silent focusing.
  • ASP – Aspherical Lenses. Lenses with this designation indicates that the lens uses at least one aspheric element. Usually, these lenses have a reduced number of component lenses and a compact size (although not necessarily), and improved performance.

Camera Bodies

Sigma is working with a new type of sensor developed by Foveon: the Foveon X3 direct image sensor. It has three layers of sensor elements, sensitive to red, green, and blue light. In essence, the sensor “sees” in RGB. The three sensor element layers take in all the color information without omissions yielding more natural colors and more detailed textures. The sensors in most DSLRs use separate pixels to detect red, green and blue light.

To date, the only DSLRs to use Foveon sensors have been made by Sigma and the sensor used has 4.65 million photosites. There are a couple of industrial cameras that use the Foveon sensors, but in the DSLR realm, Sigma is the only company using them. The pixel count is multiplied by three because each site generates signals for red, green and blue. Sigma and Foveon call this a 14.1MP sensor. Though you can’t really directly compare it with a conventional 14MP sensor (using a Bayer color matrix). Tests show that a 4.65MP Foveon sensor generates higher image quality than a 4.65MP conventional sensor, but it’s not really equal to a 14MP conventional sensor. Perhaps it’s more closely equivalent to a 10MP Bayer matrix sensor. The comparison is difficult because it depends if you look at B&W resolution or color resolution, and it depends on the quality software used to eliminate moire patterns, which tend to be much stronger with conventional Bayer matrix sensors.
In some respects the 4.65MP (or 14.1MP) Foveon sensor may be better than a 10MP conventional sensor, in some respects it may be worse. It’s certainly interesting technology, though it really hasn’t caught on with any DSLR manufacturers aside from Sigma.

Discontinued Camera Bodies

  • Sigma SD14

Search the Photo.net Classifieds for discontinued Sigma cameras, lenses, and accessories.


The lens offerings from Sigma are available in various mounts for the major camera brands: Canon, Nikon, Olympus, Sony. Take a look at the individual System guides for the major brands to help you decide on the best digital camera body.

To enhance your search for the perfect lenses for your camera gear bag, check out our guide on Building a Lens Kit.

Normal Lenses

A normal lens is light in weight and approximates the perspective of the human eye. Normal lenses generally have large maximum apertures, indicated by small f-numbers such as f/1.4 or f/1.8, and thereby gather much more light than zoom lenses. It may be possible to take a photo with a normal lens in light only 1/8th or 1/16th as bright as would be required for the same photo with a consumer-priced zoom lens. Also, the viewfinder will be brighter and therefore easier to use in dim light, due to the fact that the large maximum aperture stays open for viewing and stops down to whatever aperture you have set just before taking the picture.

The Sigma lenses appropriate for a full-frame sensor or 35mm film camera are denoted with a “DG”. The Sigma lenses appropriate for small-frame sensor cameras are denoted with a “DC”. You can use DG lenses on crop sensor cameras but you can’t use DC lenses on full frame cameras without vignetting.

Further notes about the 30/1.4: A Normal Lens for Low Light Photography
(by Philip Greenspun)

Most of the world’s great photographs were taken with fixed focal length lenses, not zooms. Partly this is because fixed or “prime” lenses are higher in every aspect of optical quality. Partly this is because a photographer with only one focal length available trains his or her eye to look for compositions that will be effective with that focal length. The “normal” perspective lens is the easiest for most beginners, because the perspective is similar to what one sees with the naked eye. On a 35mm film camera or full-frame sensor digital camera, the normal lens is a 50mm. On a small-sensor digital SLR camera, e.g., Canon Rebel XT or Nikon N70s, the equivalent would be a 30mm lens. Nikon and Canon both make wonderful 50mm prime lenses, but neither company makes a 30mm prime lens. That’s why this Sigma lens, which costs around $450, is such a great find.

If your kit zoom lens has a maximum aperture of f/4, that means you will need 8 times as much light to take a photo as you would need with the Sigma 30/1.4 set to f/1.4. With your kit lens, you must turn on the flash indoors, blasting everyone with an unflattering central light. With the Sigma, you keep the flash off and capture the light that you see with your eyes.

One added bonus of the Sigma 30/1.4 is that it has an “HSM” or “hypersonic” motor. This is equivalent to Canon’s “USM” (ultrasonic motor) or Nikon’s “SWM” (silent-wave motor) and allows the photographer to use autofocus, but adjust the focus manually if desired.

Wide-to-Telephoto Zoom

A wide-to-tele zoom is what you get as a standard “kit” lens with a consumer-grade digital SLR body. The range goes from moderately wide through normal to moderately telephoto. They are good when you are too busy to change lenses, e.g., at a wedding reception. A 16mm focal length at the wide end will capture a table of guests; the 45-55mm long end is good for a flattering portrait. The main weakness of these lenses is that the cheaper ones have a very small maximum aperture, e.g., f/4 or f/5.6, and can only be used in bright light, on a tripod, or with a blast of on-camera flash that is not very flattering.

  • Sigma 17-70mm f/2.8-4.5 DC Macro
  • Sigma 17-70mm f/2.8-4.5 DC Macro HSM
  • Sigma 18-50mm f/2.8 EX DC Macro
  • Sigma 18-50mm f/2.8 EX DC Macro HSM
  • Sigma 18-50mm f/3.5-5.6 DC
  • Sigma 18-50mm f/3.5-5.6 DC HSM
  • Sigma 18-125mm f/3.8-5.6 DC OS
  • Sigma 18-125mm f/3.8-5.6 DC OS HSM
  • Sigma 18-200mm f/3.5-6.3 for Nikon, (buy from Amazon)
  • Sigma 28-300mm f/3.5-6.3 DG

Further notes about the 18-50mm f/2.8: if you like a mid-range zoom, let it be a good one (by Philip Greenspun)

The kit zoom lenses are too slow, with maximum apertures of f/4 or f/5.6, and too cheap optically. The consequences are that you need to use a flash more of the time and your pictures lack contrast and sharpness. The best solution to both problems is a set of prime lenses, but these can be cumbersome to carry around and change. If you like the idea of a single zoom lens for walking around, the Sigma 18-50mm F2.8 EX DC is a reasonable choice at around $500.

Canon does not make a lens like this. Their fast f/2.8 zooms tend to be designed for film and full-frame sensor digital cameras such as the EOS 5D. Nikon makes a 17-55/2.8 lens that is very high quality, but it is more than twice the price of the Sigma.

This range of focal lengths is good for photographing a wedding reception or other social event.

Wide-angle Zoom Lenses

Further notes about the 10-20mm f/4-5.6: Sigma’s super wide angle zoom (by Philip Greenspun)

If you want to experiment with ultra wide angle photography and not spend more than about $500, the Sigma 10-20 is a reasonable choice. The Canon and Nikon equivalents either don’t go as wide, are more expensive, or both. Because of its slow maximum aperture, f/4 to f/5.6, this is a lens to be used outdoors or on a tripod. [If you have a Canon Digital Rebel or similar small-sensor Canon EOS body, and can stretch your budget to $700, the Canon 10-22/3.5-4.5 zoom lens is a better performer.]

Standard Zoom Lenses

On a full-frame sensor camera, the standard zoom lens offers a great perspective for wedding and event photography. From a moderate wide to moderate telephoto, the range covered is flexible and very useful. They are also good when you are too busy to change lenses, such as at a wedding reception or a social event. The 24mm focal length at the wide end will cover a flattering perspective of the wedding party formals; the 60 or 70mm long end is good for portraits. Make sure you test before you buy. Whether you’re a Canon, Nikon, Pentax, Sony, or Olympus photographer, compare the equivalent lens by the manufacturer to the Sigma to see if the money you are saving is not compromising image quality.

  • Sigma 24-60mm f/2.8 EX DG
  • Sigma 24-70mm f/2.8 EX DG
  • Sigma 24-70mm f/3.5-5.6 HF
  • Sigma 28-70mm f/2.8 EX DG
  • Sigma 28-70mm f/2.8-4 DG

Telephoto Zoom Lenses

Telephoto zoom lenses offer flexibility at a distance. Whether you are photographing wildlife or sports/action, it’s helpful to have a flexible rather than a fixed focal length. However, on some lenses this could mean a compromise in sharpness and image quality on either end, since the lens is covering a wider range. Also, some lenses are slower and will work best during daylight hours.

  • Sigma 50-500mm f/4-6.3 EX DG APO HSM
  • Sigma 50-150mm f/2.8 APO EX DC HSM
  • Sigma 55-200mm f/4-5.6 DC
  • Sigma 55-200mm f/4-5.6 DC HSM
  • Sigma 70-200mm f/2.8 APO EX DG Macro HSM
  • Sigma 70-300mm f/4-5.6 DG Macro
  • Sigma 70-300mm f/ APO DG Macro
  • Sigma 80-400mm f/4.5-5.6 EX DG OS
  • Sigma 100-300mm f/4 EX DG IF
  • Sigma 100-300mm f/4 EX DG IF HSM
  • Sigma 120-300mm f/2.8 DG
  • Sigma 120-400mm f/4.5-5.6 APO DG OS HSM
  • Sigma 135-400mm f/4.5-5.6 APO DG
  • Sigma 150-500mm f/5-6.3 APO DG OS HSM
  • Sigma 200-500mm f/2.8 APO EX DG
  • Sigma 300-800mm f/5.6 DG

Wide-angle Prime Lenses

Wide-angle lenses let you get close to your subject while still showing a lot of background information. A dramatic wide angle for a small-sensor DSLR is 16mm or shorter (calculating the multiplication factor). Fisheye lenses can add some cool effects to a photograph if you’re into that type of image. For most applications, however, such as wedding, event, and architectural photography, you may want to go with a non-fisheye wide-angle prime lens approach, such as the Sigma 20mm/1.8 or the Sigma 24mm/1.8.

  • Sigma 4.5mm f/2.8 EX DC Circular Fisheye HSM
  • Sigma 8mm f/3.5 EX DG Circular Fisheye
  • Sigma 10mm f/2.8 EX DC Fisheye
  • Sigma 10mm f/2.8 EX DC Fisheye HSM
  • Sigma 15mm f/2.8 EX DG Diagonal Fisheye
  • Sigma 20mm f/1.8 EX DG
  • Sigma 24mm f/1.8 EX DG Macro
  • Sigma 28mm f/1.8 EX DG

Telephoto Prime Lenses

A telephoto prime lens offers excellent image quality at long focal lengths due to a large maximum aperture and magnification of the subject, and can be handheld in low-light situations. When comparing a telephoto prime to a normal-to-telephoto zoom, although zoom lenses cover wide ranges, they usually have a smaller maximum aperture on the long end. Keep in mind that on a crop sensor, the effective focal length of a telephoto prime is multiplied by 1.5.

  • Sigma 300mm f/2.8 APO EX DG
  • Sigma 500mm f/4.5 APO EX DG HSM
  • Sigma 800mm f/5.6 APO EX DG HSM

Macro Lenses

Macro lenses let you photograph physically small objects. The longer the focal length of the macro lens, the more space you can put between the camera and the subject. Extra working distance is helpful in lighting scenes or keeping insects calm. A macro lens that goes down to “1:1” can be used to take a frame-filling photo of something that is roughly 23×16mm in size, the dimensions of the APS-C sized sensor on a Pentax digital body. The macro lenses below can be used for ordinary photographic projects as well, i.e., they will focus out to infinity if desired.

  • Sigma 50mm f/2.8 EX DG
  • Sigma 70mm f/2.8 EX DG
  • Sigma 105mm f/2.8 EX DG
  • Sigma 150mm f/2.8 APO EX DG
  • Sigma 180mm f/3.5 APO EX DG

Further notes about the The Sigma 150 Macro/Portrait Lens (by Philip Greenspun)

If you are serious about taking pictures of people or pictures of small objects, you will want a single focal length or “prime” lens. The longer or “telephoto” macro lenses can serve both roles. Canon and Nikon both make some long macro lenses with fabulous performance, but they cost more than $1000. Sigma’s is excellent and only around $600.

A shorter macro lens, e.g., 60 or 100mm, will be cheaper, but you’ll need to get closer to your subject. In the case of hummingbirds and insects, this might well be so close that they become disturbed. A shorter portrait lens will also be cheaper, but won’t flatten your subjects features in as flattering a manner. The bigger your subject’s nose, the farther away you need to stand when taking the picture and therefore the longer lens you need.

This lens permits focusing down to a 1:1 image size. This means that you can take frame-filling pictures of objects as small as the film or digital sensor on your camera. If you have a small sensor camera, objects as small as 15×22mm in size will fill the frame.

Note that this lens covers a full 24×36mm frame and therefore will work on any digital or film SLR, including the Canon EOS 5D.


Straight ahead on-camera flash blasts the subject with an unflattering light. Pictures will look just as you saw them with your eyes. The built-in flash of Sigma bodies only points forward and is therefore mostly useful outdoors for filling in harsh shadows. For more natural lighting, it’s best to use an accessory flash either with a TTL cord for the option of side lighting or tilted towards the ceiling for better diffusion.

  • Sigma EF-530 DG
  • Sigma EF-500 DG
  • Sigma EM-140 DG Macro Ring

To enhance your search for the perfect lenses for your camera gear bag, check out our guide on Building a Lens Kit.


For a camera body and one lens, the average professional photographer would not use a case at all. To hold a camera system, it is best to visit a nearby professional camera shop and see how your gear fits in various bags. See the photo.net camera bag article for some ideas.


Example Sigma Photographs

Normal Lenses


Wide-to-Telephoto Zoom Lenses

Wide-angle Zoom Lenses

Standard Zoom Lenses

Telephoto Zoom Lenses

Telephoto Prime Lenses

For the complete catalog of Sigma products and Sigma-related articles, forum threads, etc, visit the SigmaCameras & Equipment Guide.

Text Hannah Thiem. Original quotes ©2008 Philip Greenspun and Bob Atkins. All photos are copyright the photographer, and may not be used without written permission.

Article revised September 2015.