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Canon EOS Digital SLR System

a photo.net guide by Philip Greenspun

Along the edge of Central Park, Manhattan, 1995. Roseate Spoonbill, Ding Darling Wildlife Refuge, Sanibel Island, Florida

The Canon EOS system of digital single-lens reflex (SLR) bodies and lenses is the standard choice among professional photographers worldwide. This page makes it easy to shop for Canon digital bodies and EOS lenses. Every component manufactured by Canon is covered, plus a few exceptionally good third-party components. If you are new to photography, you might want to start with our article "Building a Digital SLR System".

This article goes through every section of the Canon EOS system and concludes with some starter system recommendations.

Canon EOS Bodies

Small sensor bodies are good for telephoto work, such as wildlife photography. A 100mm telephoto lens that would be ideal for portraits on a film or full-frame sensor body gives a 150mm equivalent perspective on a small sensor ("APS-C") body. The full-frame sensor bodies are good for wide angle photography, low-light photography, and ultimate image quality.

For nostalgia buffs, Canon still makes some film bodies that work with all of the lenses below, except those marked "small sensor only". And older Canon film bodies that

An EOS-3 is good enough for almost any photographic purpose, it is incredibly rugged, and you should be able to buy one cheap in the photo.net classifieds.

Nomenclature

F-number: lower is better.

IS is "image stabilization", a technology lifted from camcorders in which the camera electronically compensates for unsteady hands. IS is especially important at long focal lengths, e.g., 200mm and above, because the lens magnifies camera shake at the same time it is magnifying the subject. An IS lens will allow you to use slower shutter speeds without introducing camera shake. The alternative to an IS lens would be mounting the camera on a tripod or using a high ISO setting, which reduces image quality but allows the use of higher shutter speeds.

USM is "ultrasonic motor". All Canon EOS-system lenses have built-in focus motors. There is no motor in the body as is the case with Nikon, for example. The cheaper Canon lenses have a motor that must be clutched out with a switch if the photographer wishes to focus manually. When using a USM lens, the photographer can push the shutter release (or a button on the rear of the camera, if a custom function is set) and let the autofocus system do its best, then touch up the focus manually by twisting the lens ring.

The L lenses are Canon's expensive lenses designed for professional photographers. An L lens will always have good optical performance, even if it is a wide-range zoom that is challenging to design. An L lens will always be mechanically tough and well-sealed against water and dust. An L lens might be very heavy and expensive. Note that there are some non-L prime (fixed focal length or non-zoom) lenses, such as the 50/1.4, that offer extremely high optical quality. The non-L Canon zoom lenses are optimized for light weight and low cost and won't be especially high in optical quality.

EF-S lenses are designed for Canon's small-sensor digital cameras, such as the Digital Rebel. The "EF" in "EF-S" is the standard Canon EOS "Electro-Focus" mount, introduced in 1987. The "-S" stands for "short back focus" and means that the lens design protrudes more deeply into the camera body. This protrusion would damage a full-frame camera's mirror, so a mechanical interlock prevents these lenses from being mounted on a standard EOS camera. An EF-S lens will work with any of the small-sensor bodies introduced since 2003, including the original Digital Rebel (300D) and the 20D.

Normal Lenses

A normal or standard lens is light in weight and approximates the perspective of the human eye. Normal lenses 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. Another advantage of the large maximum aperture is that the viewfinder will be correspondingly brighter and therefore easier to use in dim light. (SLRs keep the lens wide open for viewing and stop down to whatever aperture you have set just before taking the picture; this is why the viewfinder always looks the same even if you switch from f/1.4 to f/8 to f/16.)

    small sensor (Rebel and 30D)

  • Sigma 30/1.4, $439, ultrasonic motor, equivalent to a 45mm perspective on a film or full-frame camera; Canon does not bother to make a competitive lens

    • full-frame sensor (EOS 5D)

  • Canon EF 50mm f/1.4 USM, $324 (review), includes an ultrasonic motor that allows simultaneous use of manual and autofocus, high quality (metal) mechanical construction
  • Canon EF 50mm f/1.8 II, $93 (review), cheap plastic case, high image quality, no ultrasonic motor and therefore autofocus is slower, noisier, and harder to override with a manual twist

In terms of flare, contrast, and sharpness, these are the highest quality lenses that you will ever attach to your camera. If you can do the job with a 50/1.4, as many of the 20th Century's greatest photographers did, you can save yourself a lot of weight and cost. There are good zoom lenses, mostly in the Canon L series, but they are very expensive and heavy.

Wide-to-Telephoto Zoom Lenses

A wide-to-tele zoom is what you get as a standard "kit" lens with a cheaper 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. The 24mm perspective (full-frame) will capture a table of guests; the 70mm or 105mm 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 gives everyone a moon face.

Here are a few photos from my brother's wedding, taken with a discontinued Canon 28-70/2.8L (superseded by the 24-70/2.8L):

Harry and Katerina's wedding. Lake Placid. September 4, 1999. Harry and Katerina's wedding. Lake Placid. September 4, 1999. Harry and Katerina's wedding. Lake Placid. September 4, 1999.

Harry and Katerina's wedding. Lake Placid. September 4, 1999. Harry and Katerina's wedding. Lake Placid. September 4, 1999.

Wide-angle Zoom Lenses

Good for general-purpose dramatic wide angle photography. More distortion than wide-angle prime lenses, which makes them less suitable for photographing architecture (though many kinds of distortion can be fixed by a PhotoShop wizard).

Telephoto Zoom Lenses

These are good complements to a normal lens when traveling. The long end may not be useful indoors due to a small maximum aperture.

Interesting third-party lenses:

  • Sigma 300-800/5.6 HSM, $7007, ultrasonic motor, good for covering an airshow where you need the range and don't have time to switch focal lengths

Wide-angle Prime Lenses

Canal Street. Manhattan 1995

These let you get close to your subject while still showing a lot of background information. Wide angle lenses are good for "environmental portraits" in which the subject occupies most of the frame, but nearby objects are in sharp focus. Photojournalism has gone gradually wider and wider over the years. A typical photo in a newspaper these days might be taken at 20-24mm on a full-frame camera.

A prime wide angle lens will have much lower distortion of vertical and horizontal lines than a zoom lens and is therefore preferred for architectural photography. All of these lenses are designed for film and full-frame sensor cameras.

Telephoto Prime Lenses

Corkscrew Swamp Sanctuary. SW Florida

A prime or fixed focal length telephoto lens offers maximum image quality, light gathering capability (aperture), and magnification. The good ones are big, heavy, and designed for use on a monopod or tripod. Sports and wildlife photography require these lenses.

The better Canon telephoto lenses are designed to work optically with the tele-extenders. Image quality will be acceptable, even at maximum aperture. As noted above, however, there is no free lunch. A tele-extender provides additional magnification, but the overall amount of light gathered by the lens remains the same. Thus, you lose one f-stop of light with the 1.4X converter and two f-stops with the 2X converter. The viewfinder will be dimmer and the camera will have a tougher time autofocusing. With the 2X converter and a slower lens, therefore, you will lose the ability to autofocus with many bodies.

These are heavy lenses. If you have a tripod quick-release system, get plates for each lens and remember to mount the lens, not the camera body, to the tripod.

Macro Lenses

Flower

Macro lenses let you fill your photograph with a subject that is physically small. The longer the focal length of the macro lens, the farther away you can be from your subject, which is important with live insects, for example. A macro lens that goes down to "1:1" can be used to take a frame-filling photo of something that is 24x36mm (1x1.5 inches) in size, the same dimensions as a frame of 35mm film or the sensor on a full-frame digital body. All Canon macro lenses, except for the MP-E 65mm, can be used for ordinary photographic projects as well, i.e., they will focus out to infinity if desired. In the old days, a lot of photographers would get a 50mm normal lens and then a 100mm macro lens that would double for use with portraits and macro projects.

If you are using a non-macro lens and need to focus closer for some reason, you can place either Canon EF 12 II Extension Tube, $78 or Canon EF 25 II Extension Tube, $130 between the body and the lens. Extension tubes move the lens farther away from the plane of the sensor. You could, for example, take pictures of just part of a person's face with a telephoto lens. If, however, you then wanted a sharp picture of a subject at infinity, you'd have to unmount the lens, remove the extension tube, and remount the lens.

Tilt-Shift Lenses

Joshua Tree National Park

The shift part of the tilt-shift lens lets you take a picture of a building, from ground level, without the lines converging and making it look as though the building is falling over. To some extent, this is obsolete because these kinds of linear distortions can be fixed post-exposure in a digital editing tool such as Adobe PhotoShop. The tilt part of a Canon tilt-shift lens lets you control the plane of sharp focus, e.g., if you want everything on a table top to be sharp. This is an effect that must be done at exposure time. A Canon tilt-shift lens lets you do many of the perspective and focus adjustments available to a photographer with a cumbersome 4x5 view camera (cloth over head, bellows in between film and lens)... at a price that is only about double what a used view camera sells for.


Flashes

Canon EOS-5, 70-200/2.8, 540EZ flash, Sto-Fen diffuser, Fuji ISO 400 color negative film

The easiest way to ruin a photograph is to use on-camera flash, which blasts the subject with an unflattering light. The resulting lack of shadows means that it is tough for a viewer to make out the features of the subject. On-camera flash is useful outdoors for filling in harsh shadows. Otherwise, the professional uses flash mostly bouncing up towards the ceiling or held as far away from the camera as possible. This is why the professional camera bodies don't incorporate the pop-top flashes the way that consumer bodies do.

Note that a standard flash, with an off-camera cord and a bit of diffusion material, may be substituted for a macro flash.

Accessories

For a camera body and one lens, the average professional photographer would not use a case at all. To hold a camera system, you should probably find a nearby professional camera shop and experiment to see how your gear fits. I usually end up preferring Tamrac and Lowe cases. Here are a few ideas:

Recommended Starter Systems

Average family:

Serious photographer:

More

Discontinued and Miscellaneous

Digital SLR Cameras
• Canon EOS 20D vs 30D vs 5D vs Nikon D200?
• Comparison of Canon 5D and Canon 20D
• CMOS Sensor Cleaning on Digital SLRs
• EOS 1D • EOS 10D • EOS 10D vs EOS 300D (Digital Rebel) • EOS 1D (Josh Root) • EOS D60 • EOS D30

Powershot Point and Shoot Cameras
• Powershot A610 • Powershot A80 • Powershot A85 • Powershot A95 • Powershot A400 • Powershot G1 • Powershot G2 • Powershot G3 • Powershot G5 • Powershot Pro1 • S100 (Digital ELPH)

35mm Film Cameras • EOS 1N • EOS 5/A2E • EOS Elan 7 • EOS Elan II • Rebel 2000 (EOS 300) • Rebel G (EOS 500N)

Lenses • EF Lens Motors • IS Lenses • How Shift Lenses Change Your Life • EF-S 18-55mm/3.5-5.6 vs. EF24-70/2.8L Shootout! • EF 20-35mm/2.8 • EF 28-70mm/2.8L • EF 35-350mm • EF 50mm/1.0 • EF 50mm/f1.4 vs. f1.8 • MP-E 65mm 1-5X Macro • EF 70-210mm/3.5-4.5 • EF 80-200mm/2.8L • EF 100mm Macro vs Tamron 90mm Macro • EF 180mm/3.5L USM Macro • EF 600mm/4L • EF 600mm/4L IS

Photo Printers • Canon SELPHY CP510 and CP710 Dye Sublimation Printers • CP-220 Compact Photo Printer • i900D Photo Printer

Scanners • Canoscan FS4000US

Accessories • BP50 Battery Pack • Speedlite 380EX

Text and pictures copyright 2005-2007 Philip Greenspun. The top left photo was taken with a 14mm lens, the widest in the Canon system, back in 1995. The top right photo in 2000 with a 600/4, the longest lens in the Canon EOS system. The photos of the Golden Retriever puppy and Samoyed were taken with an EOS 5D and 50/1.4 normal lens.

Article revised April 2008.