The Canon EF-S 17-85mm f/4-5.6 IS USM Lens is a significantly better lens than the significantly less expensive Canon EF-S 18-55mm f/3.5-5.6 Lens, and better than the Canon EF-S 18-55mm f/3.5-5.6 IS Lens, but it is not optically the equivalent of the Canon EF-S 17-55mm f/2.8 IS USM Lens or some of the L-Series lenses in similar focal length ranges. The Canon L Series Lenses will provide better sharpness (especially in the corners) and contrast at equivalent apertures in addition to having better build quality. Light fall-off is not present in these lenses at 1.6x field of view, CA is better controlled ... While not an L lens, the 17-55 is at least as good optically.
But, the Canon EF-S 17-85mm f/4-5.6 IS USM Lens is going to be the right lens for a lot of people. With its wide 5x zoom range, the 17-85 makes a great walk-around lens. There is a huge range of subject matter that fits nicely in this focal length range. And in addition to being relatively small and light, the 17-85's image quality is quite good.
Optical performance is also not L-class, but reasonable. Center sharpness is very good at all focal lengths and improves very little when stopped down. Some corner softness is present at most focal lengths and apertures.
Light fall-off is noticeable until stopped down or zoomed out to 35mm or so. Barrel distortion is very noticeable at 17mm and is also mostly gone by 35mm or so. CA (Chromatic Aberation) is very strong at 17mm, well controlled through the mid focal lengths and again visible at 85mm.
Flare is only moderately controlled. Vignetting is apparent on the wide end of the focal length range until stopped down.
Since the Canon EF-S camera bodies feature a 1.6x field of view crop factor, the Canon EF-S 17-85mm f/4-5.6 IS USM Lens has the equivalent field of view/framing to a 27.2-136mm lens on a full-frame camera body - nearly equivalent to the Canon EF 28-135mm f/3.5-5.6 IS USM Lens. My observations are that this lens also performs optically similar to the 28-135. The two lenses are very similar in size - the 17-85 measures 3.6" x 3.1" (92mm x 78.5mm) (lxd) and weighs 16.1 oz (475 g). Build quality is similar as well. The two primary differences between these lenses are the focal length range and the newer image stabilization system in the 17-85.
The background blur quality you do get with the Canon EF-S 17-85mm f/4-5.6 IS USM Lens is fine. Curved aperture blades are partly responsible for this feature. Out of focus highlights retain round shapes even when the 17-85 is stopped down.
With ring USM, the 17-85 IS focuses very fast - and very quietly. FTM (Full Time Manual) focusing is enabled in AF mode. IS on this lens is also quiet while engaged. There is a noticeable click when IS is started and stopped, but only a quiet hum is audible while IS is functioning.
The Canon EF-S 17-85mm f/4-5.6 IS USM Lens utilizes an extending but non-rotating front element. The non-rotating design feature is appreciated by Circular Polarizer Filter and split ND (Neutral Density) Filter users.
Although not a macro lens, the Canon EF-S 17-85mm f/4-5.6 IS USM Lens focuses down to 1.15' (.35m) for a MM (Maximum Magnification) of .2x. Close enough to fill the lens with smaller
The Canon EF-S 17-85mm f/4-5.6 IS USM Lens combines a very useful zoom range withimage stabilization in a light and well-performing package.
Keep in mind that the Canon EF-S 17-85mm f/4-5.6 IS USM Lens is an "EF-S" lens and only works on EF-S compatible Canon EOS bodies such as the 20D, 30D, 40D and Digital Rebel Series. EF-S is Canon's moniker for Short Back Focus. The distance between the film (sensor) plane and the rear of the lens is shorter than in an EF lens. Many question the longevity of this standard. My expectation is that it will be around for a long time - easily long enough for most people to get their desired value from a lens.
There also seems to be confusion about how the 1.6x Field of View Crop Factor (FOVCF) relates to EF-S lens framing. The answer is that you still need to apply the "focal length multiplier" to get the conventional 35mm equivalent field of view. The focal length is based on physical design of the optics. Yes, even though the lens is designed for 1.6x FOVCF digital bodies, the framing is still equivalent to a longer focal length lens on a full frame body.
Why put Image Stabilization into a wide angle to short telephoto zoom lens? For the same reason you put it into telephoto lenses - to reduce camera shake. Since the Canon EF-S 17-85mm f/4-5.6 IS USM Lens has third generation IS, it can be handheld up to 3 f-stops lower than a non-IS lens at the same focal length. Granted, a wide angle lens can be handheld at lower shutter speeds than a long telephoto lens, but being able to hold them at even lower shutter speeds is a great benefit to me. It also compensates some for the slow/narrow wide open aperture. This lens can be handheld at slow enough shutter speeds to allow significant subject motion blur when desired - such as moving water. The moving water pictures in the 17-85 IS sample gallery were all shot handheld - down to 1/3 second.
IS on this lens also allows for a very large DOF (Depth of Field) while shooting handheld.Landscape photography is one style of photography that benefits from this feature.
RIXUS 80 IS specifications
| Street price | • US: $250 • UK: £210 |
|---|---|
| Naming | SD 1100 IS Digital ELPH (US) |
| Sensor | • 1/2.5 " Type CCD |
| Image sizes | (L) 3264 x 2448, (M1) 2592 x 1944, (M2) 2048 x 1536, (M3, Date Stamp) 1600 x 1200, (S) 640 x 480, (W) 3264 x 1832. Resize in playback (M3, S, 320 x 240) |
| Movie clips | • (L)640 x 480, 30fps/60fps |
| File formats | • JPEG (EXIF 2.2) • AVI [Motion JPEG compression + WAVE (monaural)] |
| Lens | • 3x optical zoom |
| Image stabilization | Yes (lens shift-type) |
| Conversion lenses | No |
| Digital zoom | up to 4x |
| Focus | TTL autofocus |
| AF area mode | • AiAF (Face Detection / 9-point) • 1-point AF (fixed to center or Face Select and Track) |
| AF assist lamp | Yes |
| Focus distance | • Normal: 12 in./30cm-infinity • Macro: 1.2 in.-1.6 ft./3-50cm (W), 1.2 in.-1.6 ft./3-50cm (T) • Digital Macro: 1.2-3.9 in./3-10cm (W) |
| Metering | • Evaluative (linked to Face Detection AF frame) • Center-weighted average • Spot (center) |
| ISO sensitivity | • AUTO |
| Exposure compensation | +/- 2 EV in 1/3 stop increments |
| Exposure bracketing | No |
| Shutter speed | • 1/60 - 1/1500 sec (factory default) • 15 - 1/1500 sec (total range - varies by shooting mode) |
| Aperture | F2.8 - 4.9 |
| Modes | • Auto • Manual • Digital Macro • Portrait • Night Snapshot • Color Accent • Color Swap • Stitch Assist • Movie |
| Scene modes | • Kids & Pets • Indoor • Sunset • Foliage • Snow • Beach • Fireworks • Aquarium • Underwater |
| White balance | • Auto (including Face Detection WB) |
| Self timer | 2 or 10 sec, custom |
| Continuous shooting | Approx. 1.3 fps (Large/Fine) |
| Image parameters | My Colors (My Colors Off, Vivid, Neutral, Sepia, Black & White, Positive Film, Lighter Skin Tone, Darker Skin Tone, Vivid Blue, Vivid Green, Vivid Red, Custom Color) |
| Flash | • Auto, Manual Flash On / Off, Slow sync, Red-Eye Reduction • Face Detection flash exposure compensation • Flash exposure lock • Range: 30cm - 3.5m (w), 2.0m (t) |
| Viewfinder | Real-image zoom optical viewfinder |
| LCD monitor | • 2.5-inch TFT • 230,000 pixels |
| Connectivity | • USB 2.0 Hi-Speed • AV out |
| Print compliance | • Pictbridge • DPOF v.1.1 • EXIF Print |
| Storage | • SD, SDHC, MMC, MMCplus, HC MMCplus. • 32MB memory card supplied |
| Power | • NB-4L Li-ion battery • Charger included • Optional AC adapter |
| Optional accessories | • Waterproof Case WP-DC22 • High-Power Flash HF-DC1 |
| Weight (No batt) | 125 g (4.4 oz) |
| Dimensions | 86.8 x 54.8 x 22.0 mm (3.4 x 2.2 x 0.9 in) |
