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The Canon EF-S 18-200mm f/3.5-5.6 IS Lens features an awesome focal length range (one that completely covers the needs of many photographers) andan excellently-performing IS system in a nicely-sized body.

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I have to lớn admit, when i saw the initial Canon press release for the 18-200 IS,I was highly skeptical that this lens could produce even reasonable optical quality throughout the focal length (FL) range.Any FL range over 5x (max FL/min FL) raises a warning flag in my mind - you just know that there will be at least some optical deficiencies.And an 11x zoom lens is just begging for optical problems.The lack of a USM AF system raised a second warning flag.Certainly Canon would put their best AF system in a lens they expect khổng lồ get decent image unique from - even mid-line lenses such as the Canon EF-S 17-85mm f/4-5.6 IS USM Lens have Ring USM AF."You get what you pay for" raised my expectations as this lens is not in the junk-priced category.I always keep an xuất hiện mind when evaluating gear - and in this case, the 18-200 IS Lens, while not perfect, performs better than I expected.

A compact one-lens-does-it-all solution is ideal for many travel needs.The 18-200 IS" arrival was timed well with some of my own travel plans - The 18-200 & the also new-at-the-same-time Canon EOS 50D accompanied me toAcadia National Park (Maine, USA) và to thủ đô new york City.These trips gave me a very good opportunity lớn put the combination to use in the field along with typical use around trang chủ and testing in the studio.

As you might expect, the focal length range is the big attraction for this lens.Use the mouse-over labels under the focal length comparison image below khổng lồ get an idea of the range of focal lengths this lens covers.

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18mm | 24mm | 50mm | 80mm | 135mm | 170mm | 200mm

No starfish were harmed in the making of this focal length comparison & aB+W 72mm Circular Polarizer filter was used for these handheld shots.

The focal length labels above correspond to lớn those marked on the lens (the 135mm-labeled shot was actually 140mm according khổng lồ the EXIF data).As the focal lengths make large increases relative to lớn the prior web1_setting (2x from 24 khổng lồ 50mm), the angle of view rapidly narrows - bringing the subject in closer.The relative increase declines at the longer focal lengths - and the rate of change slows.The lens does not physically extend as fast above 135mm & the net change in angle of view from 170 khổng lồ 200mm is very small.

Too small of a change?Well, my Canon EF 200mm f/2.8L II USM Lensframes a 47.25" x 31.5" (1200 x 800mm) thử nghiệm target at 424.88" (10792mm) while the 18-200 IS frames the same target at 369.88" (9395mm) at the 200mm web1_setting (both lenses mounted on a 50D).The Canon EF 200mm f/2.0L IS USM Lens frames the same target at 425.12" (10798mm) with a 50D.The 18-200 is 87% as far away when framing this subject size - making its 200mm seem more lượt thích 174mm at its longest web1_setting at this moderate distance.Regardless, the EF-S 18-200"s focal length range is really nice.

When using short focal length range zoom lenses, the widest and longest focal lengths are often utilized the most.Because of its extreme range, the 18-200 stays away from the ends a much higher percentage of the time (in my use at least).It is really nice khổng lồ not be focal-length-constrained.

Also nice is the Canon EF-S 18-200mm f/3.5-5.6 IS Lens" kích cỡ and weight.It is not as light as the Canon EF-S 18-55mm f/3.5-5.6 IS Lens,but similar lớn many other mid-range zooms.

ModelWeightDimensions w/o HoodFilterYear
Canon EF 17-40mm f/4.0L USM Lens16.8 oz(475g)3.3 x 3.8"(84 x 97mm)77mm2003
Canon EF-S 17-55mm f/2.8 IS USM Lens22.8 oz(645g)3.3 x 4.4"(84 x 111mm)77mm2006
Canon EF-S 17-85mm f/4-5.6 IS USM Lens16.8 oz(475g)3.1 x 3.6"(79 x 92mm)67mm2004
Canon EF-S 18-55mm f/3.5-5.6 IS Lens7.1 oz(200g)2.7 x 2.8"(69 x 70mm)58mm2007
Canon EF-S 18-200mm f/3.5-5.6 IS Lens21.0 oz(595g)3.1 x 4"(79 x 102mm)72mm2008
Canon EF 28-135mm f/3.5-5.6 IS USM Lens19.1 oz(540g)3.1 x 3.8"(78 x 97mm)72mm1998
Canon EF 28-200mm f/3.5-5.6 USM Lens17.6 oz(500g)3.1 x 3.5"(78 x 90mm)72mm2000
Canon EF 28-300mm f/3.5-5.6L IS USM Lens59.0 oz(1670g)3.6 x 7.6"(92 x 194mm)77mm2004
Canon EF-S 55-250mm f/4-5.6 IS Lens13.8 oz(390g)2.8 x 4.3"(70 x 108mm)58mm2007

The outside of the 18-200 IS is mostly zoom ring.There is a small area khổng lồ grasp the back of the lens for mounting/dismounting, but 2.2" (55.9mm) of the lens barrel is zoom ring.This kiến thiết works well in my opinion - it is very easy to find the part of the lens you will use most frequently.The zoom ring turns smoothly and has very little play in it.

Like most zoom lenses và as I mentioned before, the 18-200 IS extends with focal length increase.The extending portion of the lens has only a slight amount of play at 18mm, but in the low khổng lồ mid focal lengths, a moderate amount of play can be felt.By 200mm, the lens is quite solid.Total extension length is 2.4" (61mm).

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Positioned above from left to lớn right in their fully retracted positions are the following lenses:Canon EF-S 18-55mm f/3.5-5.6 IS II LensCanon EF-S 15-85mm f/3.5-5.6 IS USM LensCanon EF-S 10-22mm f/3.5-4.5 USM LensCanon EF-S 18-135mm f/3.5-5.6 IS LensCanon EF-S 18-200mm f/3.5-5.6 IS LensCanon EF-S 55-250mm f/4-5.6 IS LensCanon EF-S 17-55mm f/2.8 IS USM Lens

The same lenses are shown below in their fully extended states with their lens hoods in place.

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Canon provides a small zoom-lock switch on the bottom of the EF-S 18-200mm lens by the mount.This position is about where your left thumb rests when shooting in landscape orientation.Gravity zooming is an issue with this lens - primarily below 135mm.Plan on needing lớn hold the zoom ring in place if shooting downward or upward.If you shoot and then chimp (review the shot on the rear LCD) with the lens downward, you will need khổng lồ either hold the zoom ring in place or readjust before you take the next shot.

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Use the mouseover labels above khổng lồ see the 18-200 IS at 18mm & 200mm, at MFD (Minimum Focus Distance) & infinity, with and without the lens hood.The one thing you will notice is that this lens does not extend with focusing - and that filters will not rotate (very helpful when using CP filters).The 18-200 most-closely resembles the Canon EF 28-200mm f/3.5-5.6 USM Lens -and they nội dung the optional petaled Canon EW-78D hood.The lens hood provides more help at 18mm than 200mm (a 200mm-specific hood would severely vignette at 18mm), but it is not large and it is easy to lớn reach a CP filter or lens cap inside of it.

No distance window or markings are provided.In reality, it is likely that few of us will miss this feature.

Xem thêm: Lỗi Tên File Không Hợp Lệ Trong Các Hoạt Động Xóa, Đổi Tên, Sao Chép, V

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The 18-200 IS is shown mounted on a Canon EOS 50D above.

Canon"s Ring USM AF is really nice - so I was disappointed when I learned that this lens did not have it.However, for a milimet (Micro Motor) AF lens, this one is not bad.Speed is reasonable and while audible, this lens is not going khổng lồ attract much attention when focusing.

FTM (Full Time Manual) focusing is not enabled on the 18-200 IS & the focus ring turns during tự động focusing.Because the zoom ring is so large và the focus ring is rather small, it is unlikely that this turning will bother you.The manual focus ring is relatively small & reasonably smooth, but has some play in it - especially around 50mm.It is far better than the 18-55 kit lenses with the tiny ring on the extending (wobbly) part of the lens.This lens is not parfocal - you will need lớn re-focus if the focal length is changed (this complicates the gravity-zoom attribute).

Most importantly, focus accuracy has been very good.Of course, accurate focusing is not especially challenging for a slow (narrow aperture) lens on a 1.6x body.Here is how the 18-200"s variable aperture steps down compared to lớn some other lenses.

Modelf/3.5f/4.0f/4.5f/5.0f/5.6
Canon EF-S 18-55mm f/3.5-5.6 IS Lens18mm24mm39mm47mm
Canon EF-S 18-200mm f/3.5-5.6 IS Lens18mm24mm40mm50mm90mm
Canon EF 28-135mm f/3.5-5.6 IS USM Lens28mm37mm50mm67mm85mm
Canon EF 28-200mm f/3.5-5.6 USM Lens28mm45mm55mm80mm
Canon EF 28-300mm f/3.5-5.6L IS USM Lens28mm50mm55mm70mm115mm
Canon EF-S 55-250mm f/4-5.6 IS Lens55mm74mm96mm154mm

Judging foreground and background blur unique is not easy - especially with a lens that has the range of focal lengths that this one has.My impression of the 18-200 is that the 6 rounded-blade aperture delivers OK but not great blur quality.I am seeing a slight donut effect in OOF (Out of Focus) specular highlights -these circles are rendered darker in the center và brighter on the border instead of being more evenly toned throughout.Here is a 200mm f/11 example.

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Wide mở cửa results were better.Stopping down an already slow lens on a 1.6x body makes getting an out of focus background somewhat challenging in the first place.

Continuing on the ever-important image unique topic ...At 18mm, CA (Chromatic Aberration) is strong mid-frame and in the corners.CA improves as the focal length is increased until basically gone at 50mm.By 135mm, CA once again begins to show mid-frame & in the corners & continues to lớn be present through 200mm.

Watch the strong barrel distortion in the middle portion of the frame at 18mm.You will want lớn keep straight lines away from the borders at this focal length; otherwise, you will see a large bump out of the center with lines straightening again near the corners.To see this, look at the green trim on the corner of the building in the example below.

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By 24mm, lines are nearly straight again, but pincushion distortion sets in by 28mm & gets relatively strong by 50mm through 200m.Another way khổng lồ gauge the amount of distortion present at various focal lengths is to lớn watch the vị trí cao nhất image in the ISO 12233 sample crop tool change kích thước as different focal lengths are selected.Also, compare the 18-200 images khổng lồ the nearly-distortion-free Canon EF 200mm f/2.8L II Lens samples for the same camera.

Flare is well-controlled overall, but shows up stronger at the longer over of the focal length range (where the lens hood is less effective).Color and contrast seem fine.

Vignetting is visible in the corners at wide open apertures.It is moderately strong at the long kết thúc of the focal length range và at 18mm.Being an "EF-S" lens, the 18-200 IS does not have the larger image circle size that a full-frame compatible "EF" lens has and therefore shows more vignetting on the EF-S compatible bodies it mounts on (all have a 1.6x FOVCF).

The Canon EF-S 18-200mm f/3.5-5.6 IS Lens is relatively sharp in the center even wide open.Stopping down to lớn f/5.6 brings nice sharpness to the center of the image through 50mm.Use f/8 from 80mm through 200mm for best center sharpness.Corners are soft wide open and need f/8 for good sharpness over most of the focal length range.Corners are decent at f/5.6 at 18mm và prefer f/11 at 135mm.Sharpness out of this lens definitely exceeded my expectations.

As noted earlier in the review, I used a Canon EOS 50D for testing this lens.Testing a lens with a new camera requires getting khổng lồ know both at the same time.One of the things I am noticing with the very high density APS-C 50D sensor is that diffraction starts eroding image sharpness by f/8.The Rebel XSi/450D is not far behind with diffraction showing just past f/8.So, what I"m saying, is that stopping down lớn f/11 delivers less-sharpness with the latest 1.6x cameras (on all lenses).This leaves a narrow range of aperture settings lớn achieve the best image unique from this lens.

With a narrow range of optimum apertures to lớn use, image stabilization becomes even more valuable because IS allows the lens khổng lồ be handheld over a much wider range of shutter speeds.And the IS system in the 18-200 IS is proving very effective.At 18mm, I am getting a very good percentage of sharp images at .6 sec. And still getting sharp shots with exposures as long as 1 second.At 200mm, I am getting solid results at 1/20 sec. With some even longer exposures resulting in sharp images.Auto-panning is featured (no switch required) - IS operation is barely audible.I"m impressed.

A relatively close 1.48" (450mm) MFD (Minimum Focus Distance) delivers a nice .24x milimet (Maximum Magnification) for the 18-200.This is a not a macro lens (in my mind at least), but will accommodate many close-up needs including flower và other similar-sized-item photography.