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The 40D is commonly available with several good, basic lenses that can serve you well as a "walk-around" lens (one you keep on the camera most of the time, especially when you're out and about without your camera bag). The number of options available to you is actually quite amazing, even if your budget is limited to about $100-$350 for your first lens. One other vendor, for example, offers only 18mm-70mm and 18mm-55mm kit lenses in that price range, plus a 24mm-85mm zoom. Two of the most popular starter lenses Canon offers are shown in Figure 6.2. Canon's best-bet first lenses are:

■ Canon EF-S 18-55mm f/3.5-5.6 Autofocus Lens. This is the least expensive option, which, depending on where you buy your camera, may add only about $100 to the purchase price of the body alone. This medium-wide to short telephoto lens (29mm-88mm full-frame equivalent) is the standard lens found on Digital Rebel models, and it is frequently sold as the basic kit lens for the EOS 40D for those on a budget. It is designed exclusively for Canon

Figure 6.2

The Canon EF-S 1855mm f/3.5-5.6 Autofocus lens (left) and Canon EF-S 1785mm f/4-5.6 IS USM Autofocus lens (right), are two of the most popular starter lenses for the EOS 40D.

Figure 6.2

The Canon EF-S 1855mm f/3.5-5.6 Autofocus lens (left) and Canon EF-S 1785mm f/4-5.6 IS USM Autofocus lens (right), are two of the most popular starter lenses for the EOS 40D.

dSLRs with a 1.6X crop factor, and it shouldn't be used on full-frame cameras (more on this later). A maximum aperture of f/5.6 at 55mm makes this a relatively slow lens that's not great for low-light shooting. You can often find the 18-55mm lens available separately for $100-$140.

■ Canon EF-S 18-55mm f/3.5-5.6 IS Autofocus Lens. This new lens, introduced at the same time as the EOS 40D, is worth the slight extra premium, because it adds image stabilization that can counter camera shake by providing the vibration-stopping capabilities of a shutter speed four stops faster than the one you've dialed it. That is, with image stabilization activated, you can shoot at 1/30 second and eliminate camera shake as if you were using a shutter speed of 1/250th second. (At least, that's what Canon claims; I usually have slightly less impressive results.) Of course, IS doesn't freeze subject motion—that basketball player driving for a lay-up will still be blurry at 1/30 second, even though the effects of camera shake will be effectively nullified. But this lens is an all-around good choice.

■ Canon EF-S 17-85mm f/4-5.6 IS USM Autofocus Lens. This lens smashes through the arbitrary $350 price barrier I set earlier, but I'm making an exception because the 17-85mm lens is probably the most popular "basic" lens sold with the 40D, despite its $500-plus price tag. The allure here is the built-in image stabilization, which allows you to shoot rock-solid photos at shutter speeds that are at least two or three notches slower than you'd need normally (say, 1/8th second instead of 1/30th or 1/60th second), as long as your subject isn't moving. It also has a quiet, fast, reliable ultrasonic motor (more on that later, too). This is another lens designed for the 1.6X crop factor; all the remaining lenses in this list can also be used on full-frame cameras. (I'll tell you why later in this chapter.)

■ Canon EF 55-200mm f/4.5-5.6 II USM Autofocus Lightweight Compact Telephoto Zoom Lens. If you bought the 18-55mm kit lens, this one picks up where that one leaves off, going from short telephoto to medium long (88mm-320mm full-frame equivalent). It's actually faster at 55mm than the basic kit lens and features a desirable ultrasonic motor. Best of all, it's very affordable at around $225. If you can afford only two lenses, the 18-55mm and this one make a good basic set.

■ EF-S 55-250mm f/4-5.6 IS Telephoto Zoom Lens. This is an image-stabilized EF-S lens (which means it can't be used with Canon's 1.3X and 1.0X crop-factor pro cameras), providing the longest focal range in the EF-S range to date, and that 4-stop Image Stabilizer. Again, it's more money than the older, non-stabilized EF version, but it's worth the extra cost.

■ Canon EF 24-85mm f/3.5-4.5 USM Auto Focus Wide-Angle Telephoto Zoom Lens. If you can get by with normal focal length to medium telephoto range, Canon offers four affordable lenses, plus one more expensive killer lens that's worth the extra expenditure. All of them can be used on full-frame or cropped-frame digital Canons, which is why they include "wide angle" in their product names. They're really wide-angle lenses only when mounted on a full-frame camera. This one, priced in the $300 range, offers a useful range of focal lengths, extending from the equivalent of 38mm to 136mm.

■ Canon EF 28-105mm f/3.5-4.5 II USM Autofocus Wide-Angle Telephoto Zoom Lens. If you want to save about $100 and gain a little reach, this 45mm-168mm (equivalent lens) might be what you are looking for.

■ Canon EF 28-135mm f/3.5-5.6 IS USM Image-Stabilized Autofocus Wide-Angle Telephoto Zoom Lens. Image stabilization is especially useful at longer focal lengths, which makes this 45mm-216mm (equivalent) lens worth its $400-plus price tag. Several retailers are packing this lens with the 40D as a kit.

■ Canon EF 28-200mm f/3.5-5.6 USM Autofocus Wide-Angle Telephoto Zoom Lens. If you want one lens to do everything except wide-angle photography, this 7X zoom lens costs less than $400 and takes you from the equivalent of 45mm out to a long 320mm.

■ Canon Zoom Wide-Angle-Telephoto EF 24-70mm f/2.8L USM Autofocus Lens. I couldn't leave this premium lens out of the mix, even though it costs well over $1,000. As part of Canon's L-series (Luxury) lens line, it offers the best sharpness over its focal range than any of the other lenses in this list. Best of all, it's fast (for a zoom), with an f/2.8 maximum aperture that doesn't change as you zoom out. Unlike the other lenses, which may offer only an f/5.6 maximum f/stop at their longest zoom setting, this is a constant aperture lens, which retains its maximum f/stop. The added sharpness, constant aperture, and ultra-smooth USM motor are what you're paying for with this lens.

What Lenses Can You Use?

The previous section helped you sort out what lens you need to buy with your 40D (assuming you already didn't own any Canon lenses). Now, you're probably wondering what lenses can be added to your growing collection (trust me, it will grow). You need to know which lenses are suitable and, most importantly, which lenses are fully compatible with your EOS 40D.

With the Canon 40D, the compatibility issue is a simple one: It accepts any lens with the EF or EF-S designation, with full availability of all autofocus, autoaper-ture, autoexposure, and image-stabilization features (if present). It's comforting to know that any EF (for full-frame or cropped sensors) or EF-S (for cropped sensor cameras only) will work as designed with your camera.

But wait, there's more. You can also attach Nikon F mount, Leica R, Olympus OM, and M42 ("Pentax screw mount") lenses with a simple adapter, if you don't mind losing automatic focus and aperture control. If you use one of these lenses, you'll need to focus manually (even if the lens operates in autofocus mode on the camera it was designed for), and adjust the f/stop to the aperture you want to use to take the picture. That means that lenses that don't have an aperture ring (such as Nikon G-series lenses) must be used only at their maximum aperture. Because of these limitations, you probably won't want to make extensive use of "foreign" lenses on your 40D, but an adapter can help you when you really, really need to use a particular focal length but don't have a suitable Canon-compatible lens. For example, I occasionally use an older 400mm lens that was originally designed for the Nikon line on my 40D. The lens needs to be mounted on a tripod for steadiness, anyway, so its slower operation isn't a major pain. Another good match is the 105mm Micro-Nikkor I sometimes use with my Canon 40D. Macro photos, too, are most often taken with the camera mounted on a tripod, and manual focus makes a lot of sense for fine-tuning focus and depth-of-field. Because of the contemplative nature of close-up photography, it's not much of an inconvenience to stop down to the taking aperture just before exposure.

The limitations on use of lenses within Canon's own product line (as well as lenses produced for earlier Canon SLRs by third-party vendors) is fairly clear-cut. The EOS 40D cannot be used with any of Canon's earlier lens mounting schemes for its film cameras, including the immediate predecessor to the EF mount, the FD mount (introduced with the Canon F1 in 1964 and used until the Canon T60 in 1990), FL (1964-1971), or the original Canon R mount (1959-1964). That's really all you need to know. While you'll find FD-to-EF adapters for about $40, you'll lose so many functions that it's rarely worth the bother.

In retrospect, the switch to the EF mount seems like a very good idea, as the initial EOS film cameras can now be seen as the beginning of Canon's rise to eventually become the leader in film and (later) digital SLR cameras. By completely revamping its lens mounting system, the company was able to take advantage of the latest advances in technology without compromise.

For example, when the original EF bayonet mount was introduced in 1987, the system incorporated new autofocus technology (EF actually stands for "electro focus") in a more rugged and less complicated form. A tiny motor was built into the lens itself, eliminating the need for mechanical linkages with the camera.


Four different lens mounts in 40-plus years might seem like a lot of different mounting systems, especially when compared to the Nikon F mount of 1959, which retained quite a bit of compatibility with that company's film and digital camera bodies during that same span. However, in digital photography terms, the EF mount itself is positively ancient, having remained reasonably stable for almost two decades. Lenses designed for the EF system work reliably with every EOS film and digital camera ever produced.

However, at the time, yet another lens mount switch, especially a change from the traditional breech system to a more conventional bayonet-type mount, was indeed a daring move by Canon. One of the reasons for staying with a particular lens type is to "lock" current users into a specific camera system. By introducing the EF mount, Canon in effect cut loose every photographer in its existing user base. If they chose to upgrade, they were free to choose another vendor's products and lenses. Only satisfaction with the previous Canon product line and the promise of the new system would keep them in the fold.

Instead, electrical contacts are used to send power and the required focusing information to the motor. That's a much more robust and resilient system that made it easier for Canon to design faster and more accurate autofocus mechanisms just by redesigning the lenses.

Today, in addition to its EF lenses, Canon offers lenses that use the EF-S (the S stands for "short back focus") mount, with the chief difference being (as you might expect) lens components that extend farther back into the camera body of some of Canon's latest digital cameras (specifically those with smaller than full-frame sensors), such as the 40D and Digital Rebels. As I'll explain next, this refinement allows designing more compact, less-expensive lenses especially for those cameras, but not for models like the EOS 5D, IDs Mark III, or 1D Mark III (even though the latter camera does have a sensor that is smaller than full frame).

Canon's EF-S lens mount variation was born in 2003, when the company virtually invented the consumer-oriented digital SLR category by introducing the original EOS 300D/Digital Rebel, a dSLR that cost less than $1,000 with lens at a time when all other interchangeable lens digital cameras (including the 40D's "grandparent," the original EOS 10D) were priced closer to $2,000 with a basic lens. Like the EOS 10D introduced earlier that same year, the Digital Rebel featured a smaller than full-frame sensor with a 1.6X crop factor (Canon calls this format APS-C).

But the Digital Rebel accepted lenses that took advantage of the shorter mirror found in APS-C cameras, with elements of shorter focal length lenses (wide angles) that extended into the camera, space that was off limits in other models because the mirror passed through that territory as it flipped up to expose the shutter and sensor. (Canon even calls its flip-up reflector a "half mirror.")

In short (so to speak), the EF-S mount made it easier to design less-expensive wide-angle lenses that could be used only with 1.6X-crop cameras, and featured a simpler design and reduced coverage area suitable for those non-full-frame models. The new mount made it possible to produce lenses like the ultra-wide EF-S 1022mm f/3.5-4.5 USM lens, which has the equivalent field of view as a 16mm-35mm zoom on a full-frame camera.

Suitable cameras for EF-S lenses include the Digital Rebel, the newer Canon EOS 350D/Digital Rebel XT/XTi, the Canon EOS 20D/30D, and, today, the EOS 40D. The EF-S lenses cannot be used on the EOS 10D, the 1D Mark II N/Mark III (which have a 28.7mm X 19.1mm APS-H sensor with a 1.3X crop factor), or any of the full-frame digital or film EOS models. It's easy to tell an EF lens from an EF-S lens: The latter incorporate EF-S into their name! Plus, EF lenses have a raised red dot on the barrel that is used to align the lens with a matching dot on the camera when attaching the lens. EF-S lenses and compatible bodies use a white square instead. EF-S lenses also have a rubber ring at the attachment end that provides a bit of weather/dust sealing and protects the back components of the lens if a user attempts to mount it on a camera that is not EF-S compatible.

Ingredients of Canon's Alphanumeric Soup

The actual product names of individual Canon lenses are fairly easy to decipher; they'll include either the EF or EF-S designation, the focal length or focal length range of the lens, its maximum aperture, and some other information. Additional data may be engraved on the barrel or ring surrounding the front element of the lens, as shown in Figure 6.3. Here's a decoding of what the individual designations mean:

■ EF/EF-S. If the lens is marked EF, it can safely be used on any Canon EOS camera, film or digital. If it is an EF-S lens, it should be used only on an EF-S compatible camera, such as the Digital Rebels, EOS 20D/30D/40D, and any newer APS-C cameras introduced after the publication of this book.

■ Focal length. Given in millimeters or a millimeter range, such as 60mm in the case of a popular Canon macro lens, or l7-55mm, used to describe a medium-wide to short-telephoto zoom.

■ Maximum aperture. The largest f/stop available with a particular lens is given in a string of numbers that might seem confusing at first glance. For example, you might see 1:1.8 for a fixed-focal length (prime) lens, and 1:4.5-5.6 for a zoom. The initial 1: signifies that the f/stop given is actually a ratio or fraction (in regular notation, f/ replaces the 1:), which is why a 1:2 (or f/2) aperture is larger than an 1:4 (or f/4) aperture—just as 1/2 is larger than 1/4. With most zoom lenses, the maximum aperture changes as the lens is zoomed to the telephoto position, so a range is given instead: 1:4.5-5.6. (Some zooms, called constant aperture lenses, keep the same maximum aperture throughout their range.)



Figure 6.3 Most of the key specifications of the lens are engraved in the ring around the front element.

■ Autofocus type. Most newer Canon lenses that aren't of the bargain-basement type use Canon's ultrasonic motor autofocus system (more on that later) and are given the USM designation. If USM does not appear on the lens or its model name, the lens uses the less sophisticated AFD (arc-form drive) autofocus system or the micromotor (MM) drive mechanism.

■ Series. Canon adds a Roman numeral to many of its products to represent an updated model with the same focal length or focal length range, so some lenses will have a II or III added to their name.

■ Pro quality. Canon's more expensive lenses with more rugged construction and higher optical quality, intended for professional use, include the letter L (for "luxury") in their product name. You can further differentiate these lenses visually by a red ring around the lens barrel and the off-white color of the metal barrel itself in virtually all telephoto L-series lenses. (Some L-series lenses have shiny or textured black plastic exterior barrels.) Internally, every L lens includes at least one lens element that is built of ultra-low dispersion glass, is constructed of expensive fluorite crystal, or uses an expensive ground (not molded) aspheric (non-spherical) lens component.

■ Filter size. You'll find the front lens filter thread diameter in millimeters included on the lens, preceded by a 0 symbol, as in 067 or 072.

■ Special-purpose lenses. Some Canon lenses are designed for specific types of work, and they include appropriate designations in their names. For example, close-focusing lenses such as the Canon EF-S 60mm f/2.8 Macro USM lens incorporate the word Macro into their name. Lenses with perspective control features preface the lens name with T-S (for tilt-shift). Lenses with built-in image-stabilization features, such as the nifty EF 28-300mm f/3.5-5.6L IS USM Telephoto Zoom include IS in their product names.


Incorporating the autofocus motor inside the lens was an innovative move by Canon, and this allowed the company to produce better and more sophisticated lenses as technology became available to upgrade the focusing system. As a result, you'll find four different types of motors in Canon-designed lenses, each with cost and practical considerations.

■ AFD (Arc-form drive) and Micromotor (MM) drives are built around tiny versions of electromagnetic motors, which generally use gear trains to produce the motion needed to adjust the focus of the lens. Both are slow, noisy, and not particularly effective with larger lenses. Manual focus adjustments are possible only when the motor drive is disengaged.

■ Micromotor ultrasonic motor (USM) drives use high-frequency vibration to produce the motion used to drive the gear train, resulting in a quieter operating system at a cost that's not much more than that of electromagnetic motor drives. With the exception of a couple lenses that have a slipping clutch mechanism, manual focus with this kind of system is possible only when the motor drive is switched off and the lens set in Manual mode. This is the kind of USM system you'll find in lower cost lenses.

■ Ring ultrasonic motor (USM) drives, available in two different types (electronic focus ring USM and ring USM), also use high-frequency movement, but generate motion using a pair of vibrating metal rings to adjust focus. Both variations allow a feature called Full Time Manual (FTM) focus, which lets you make manual adjustments to the lens's focus even when the autofocus mechanism is engaged. With electronic focus ring USM, manual focus is possible only when the lens is mounted on the camera and the camera is turned on; the focus ring of lenses with ring USM can be turned at any time.

Your Second (and Third...) Lens

There are really only two advantages to owning just a single lens. One of them is creative. Keeping one set of optics mounted on your 40D all the time forces you to be especially imaginative in your approach to your subjects. I once visited Europe with only a single camera body and a 35mm f/2 lens. The experience was actually quite exciting, because I had to use a variety of techniques to allow that one lens to serve for landscapes, available light photos, action, close-ups, portraits, and other kinds of images. Canon makes an excellent 35mm f/2 lens (which focuses down to 9.6 inches) that's perfect for that kind of experiment, although, today, my personal choice would be the sublime Canon Wide-Angle EF 35mm f/1.4L USM Autofocus lens.

Of course, it's more likely that your "single" lens is actually a zoom, which is, in truth, many lenses in one, taking you from, say, 17mm to 85mm (or some other range) with a rapid twist of the zoom lever. You'll still find some creative challenges when you stick to a single zoom lens's focal lengths.

The second advantage of the unilens camera is only a marginal technical benefit since the introduction of the EOS 40D. If you don't exchange lenses, the chances of dust and dirt getting inside your 40D and settling on the sensor is reduced (but not eliminated entirely). Although I've known some photographers who minimized the number of lens changes they made for this very reason, reducing the number of lenses you work with is not a productive or rewarding approach for most of us. The 40D's automatic sensor cleaning feature has made this "advantage" much less significant than it was in the past.

It's more likely that you'll succumb to the malady known as Lens Lust, which is defined as an incurable disease marked by a significant yen for newer, better, longer, faster, sharper, anything-er optics for your camera. (And, it must be noted, this disease can cost you significant yen—or dollars, or whatever currency you use.) In its worst manifestations, sufferers find themselves with lenses that have overlapping zoom ranges or capabilities, because one or the other offers a slight margin in performance or suitability for specific tasks. When you find yourself already lusting after a new lens before you've really had a chance to put your latest purchase to the test, you'll know the disease has reached the terminal phase.

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Digital Camera and Digital Photography

Digital Camera and Digital Photography

Compared to film cameras, digital cameras are easy to use, fun and extremely versatile. Every day there’s more features being designed. Whether you have the cheapest model or a high end model, digital cameras can do an endless number of things. Let’s look at how to get the most out of your digital camera.

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