Pros: Ultra-compact, 8 megapixels, fast, stylish, user friendly, 3.0" LCD screen, and Optical Image Stabilization
Cons: Auto exposure only, no optical viewfinder, and red-eye issues
The bottom line: Canon's new PowerShot SD870 IS digital camera provides a near perfect balance of pocketability, auto everything operation, snappy performance, and tough as nails durability.
Canon's ultra-compact digicams have consistently been among the most successful competitors in the hi-tech marketplace because they (almost) always deliver impressive usability, class champ performance, and very good image quality - all stuffed into a stylish metal alloy body that's small enough to be dropped into a shirt pocket and tough enough to go just about anywhere. The new SD870 IS (the same camera is sold as the IXUS Digital 860 IS in Europe/Africa and the IXY Digital 910IS in Japan/Asia) doesn’t deviate from that winning formula.

The SD870 IS replaces Canon’s very popular SD850/IS, but the changes are minor. The SD870 IS looks slightly different from its predecessor and features a bit more resolution (8 megapixels versus 7), a bigger LCD screen (3.0 inches versus 2.5 inches), the ability to record longer video clips, and a lower MSRP. On the negative side of the update scale the SD850 IS’s optical viewfinder has gone the way of the Dodo – displaced (evidently) by the SD870 IS’s larger LCD screen.

NUTS & BOLTS

Viewfinder/LCD

Like most of its competition, the SD870 IS doesn’t provide an optical viewfinder – framing and composition must be accomplished via the LCD screen.

The SD870 IS's 3.0 inch (wide viewing angle) amorphous silicon TFT LCD screen completely dominates the camera's rear deck. LCD images are bright, relatively sharp (230,000 pixels), hue (color) accurate, generally fluid, and the display gains "up" (automatically brightens) in dim lighting - users can also manually boost LCD screen brightness. The LCD screen shows 100% of the image frame and is useable (barely) in bright outdoor lighting. The LCD info/status display provides all information the camera’s target audience is likely to need.

In Playback mode, a histogram display provides a graphic readout of the tonal distribution range of captured image and that’s helpful in determining over or under exposure (allowing the image to be re-shot), but a live histogram would have been better. The SD870 IS also provides a user selectable Grid Line Display to help with composition.

Zoom Lens

The Canon PowerShot SD870 IS is equipped with the same f2.8-f5.8/4.6mm-17.3mm (28mm-105mm equivalent) optical zoom that graced its predecessors. Ultra-compact digicam zooms generally start at around (the equivalent of) 35mm, so a true wide angle (great for group shots in tight indoor venues and traditional landscapes) POV gives the SD870 IS a nice edge over most of its competition. When the camera is powered up, the lens automatically telescopes out of the camera body. When the camera is powered down the lens is fully retracted into the camera body and a built in (iris style) lens cover slides into place to protect the front element.

Zoom operation is fast, smooth, and fairly quiet, but this lens exhibits noticeable barrel distortion (straight lines bow out from the center) at the wide-angle end of the zoom and very minor pin cushioning (straight lines bow in toward the center) at full telephoto. There is visible softness in the corners, but no vignetting (dark corners). Chromatic aberration (purple fringing) is well controlled. Colors are bold, bright, slightly over saturated, and hue accurate, but native (default) contrast is a bit on the hard side. Minimum focusing distance (in Macro mode) is 1.2 inches/3.0 centimeters – close enough for frame filling bugs and flowers shots.

Optical Image Stabilization (OIS)

For the diminutive SD870 IS Canon relies on a miniaturized version of the Optical Image Stabilization (IS) system used in their dSLR IS lenses. This Optical Image Stabilization system reduces blur by quickly and precisely shifting lens elements in the SD870 IS’s tiny zoom to compensate for camera movement. OIS allows photographers to shoot at shutter speeds up to three stops slower than would have been possible without OIS. For example, if a shutter speed of 1/500th of a second is required to avoid the effects of camera shake (without OIS) a digicam with OIS can capture a reasonably sharp image of the same subject (everything else being equal) at 1/60th of a second. OIS provides an especially important benefit when shooting handheld outdoors in good light at full telephoto - where even the slightest camera movement is magnified. Image stabilization is also be very useful when shooting indoors - where higher shutter speeds may not be possible or would result in dark images with poor shadow/highlight detail. In addition, Image stabilization combined with higher sensitivity settings (like the SD870 IS’s 800 ISO and 1600 ISO settings) can dramatically increase exposure options in low/natural light and dimly lit indoor venues where flash use is often prohibited.

The SD870 IS provides three IS modes (plus off): Continuous (IS is on full time), 'Shoot only' (IS is only activated when the picture is taken) and Panning (IS only stabilizes up and down motion) for horizontally panned exposures. The SD870 IS's Image Stabilization system works nicely, but it won’t do magic tricks - like neutralizing sharp camera movements or reducing blur caused by super quick moving subjects.

Auto Focus (AF)

The SD870 IS recycles the same TTL Contrast Detection 9 point AiAF (Advanced intelligent Auto Focus) system used on earlier digital elph models. The AiAF system analyzes the scene in front of the camera and then calculates camera to subject distance to determine which of the 9 AF points is closest to the primary subject and then automatically locks focus on that AF point (closest subject priority), even when the subject is not centered in the viewfinder.

The SD870 IS also features Face Detection AF/AE technology – just point the camera at the subject(s) and press the shutter button halfway. Face Detection AF will locate, lock on, and track up to nine faces in the image frame. Face Detection AF selects the optimum subject based on Canon’s ISAPS (Intelligent Scene Analysis based on Photographic Space) technology and closest focus priority and then optimizes all exposure parameters just before the image is recorded.

The Canon PowerShot SD870 IS also provides an AF assist beam for quicker and more accurate focusing in dim/low light.

Flash

The SD870 IS's built-in multi mode flash (not surprisingly in view of the camera’s tiny footprint) is pretty weak. Flash options include: Auto (fires when needed), On (fill flash), Red-Eye Reduction, Slow Synch, and off. Canon claims the maximum flash range (at the wide angle end of the zoom) is (Auto ISO) 13.12 feet/4.0 meters, but realistically anything beyond 8-10 feet is going to be fairly dark unless shot against light colored backgrounds with lots of ambient lighting (or at the High ISO setting with IS engaged). Canon's optional HF-DC1 auto (slave) flash unit works in combination with the built-in flash and extends maximum flash range to about 30 feet.

The SD870 IS’s DIGIC III processor continually adjusts sensitivity/ISO to keep the flash synch (shutter speed) at 1/60th of a second to maintain a practical balance of ambient lighting and artificial lighting.

Like all ultra-compact digicams the SD870 IS’s built-in flash (due to the constraints of miniaturization) is positioned very near and on essentially the same plane as the lens, so redeye will be an ongoing problem. Shooters can rely on the red-eye reduction mode or defeat redeye by disabling the flash and relying on the IS system – a shake stabilized slower shutter speed will cover most lighting situations and naturally lit portraits always look better than flash lit portraits.

The built-in flash is essentially useless up-close (nearer than 12 inches) and that may present problems for macro shooters. Macro fans can shoot close ups (with flash) at the telephoto setting (minimum focusing distance at the telephoto end of the zoom is 12 inches) or rely on the IS system to shoot (without flash) at slower shutter speeds. Flash recycle time (with a fully charged NB-5L and red-eye reduction off) is between 5 and 7 seconds.

Memory Media

The SD870 IS saves images to SD/SDHC/MMC memory media. Canon includes a 32MB starter SD card with the camera.

Image File Format(s)

JPEG only

Connectivity

USB 2.0 (HS) out, A/V out, DC in (optional)

Power

The Canon PowerShot SD870 IS draws its juice from Canon’s NB-5L 3.7V 1120mAh Lithium-ion rechargeable battery pack. Canon claims the SD870 IS is good for up to 270 exposures. I didn't keep track of my exposures versus power depth, but I’m guessing (based on how I used the camera – full time LCD, lots of pre-focus and hold for the decisive moment, occasional flash use, shoot only IS, and heavy review/delete/re-shoot) that a fully charged NB5L is good for something like 150-200 exposures.

Shooters who plan on taking the SD870 IS along on extended trips or for long weekends away should probably purchase a back up battery. The included charger needs about two hours to juice an empty NB-5L back up to full power.

EXPOSURE

The Canon PowerShot SD870 IS (like its predecessor and siblings) provides users with a remarkably simple auto exposure system. The camera’s integrated auto exposure system (iSAPS is coupled to the DIGIC III processor and AiAF auto focus system) does much more than just average exposure data - so most recorded images are noticeably better than average. Canon's iSAPS (intelligent Scene Analysis based on Photographic Space) technology produces dependably very good to excellent images in all Scene modes. The camera instantly matches the scene in front of the lens with an on board database of known scene types and then compares that information with the specific scene’s subject distance, white balance, contrast range, lighting, and color (just before the image is recorded) to determine the best exposure. Exposure options include Full Auto, 10 Scene modes (Portrait, Foliage, Snow, Beach, Fireworks, Aquarium, Underwater, Indoor, Kids & Pets, and Night Snapshot), Manual mode (which is actually Programmed AE mode since the camera always controls aperture and shutter speed settings), and Movie mode.

Movie Mode

SD870 IS users can record video clips (with mono audio) at 640x480 @ 30 fps up to 4Gb (with a high speed SD card). The camera can also record up to 60 seconds of fast frame rate (320X240) @ 60 fps video clips and several lower resolution video options. In addition, the SD870 IS provides a voice-notation mode that allows users to add audio notes (up to 60 seconds) to their still image files.

Metering

The SD870 IS's default evaluative light measurement system is dependably accurate in most lighting - so casual shooters won't have to worry about metering. More experienced photographers can opt for either Spot metering or Center-weighted Averaging metering for more demanding/creative compositions. Like all ultra-compact digicams, the SD870 IS's has some dynamic range (from deep shadows to bright highlights) shortcomings because the diminutive1/2.5" CCD sensor just can’t capture the full tonal range – so the SD870 IS’s evaluative/default metering system is calibrated to preserve shadow detail at the expense of highlight detail and that built-in exposure bias results in occasional clipping (burnt out highlights).

White Balance (WB)

The Canon PowerShot SD870 IS provides users with an adequate selection of white balance options - WB settings include: TTL Auto, Daylight, Cloudy, Tungsten, Fluorescent, Flourescent H, and a custom (manual) mode that allows shooters to use a white/gray card (or white wall or ceiling) to insure accurate color. At the auto WB setting the SD870's native color interpolation is (hue) accurate, but slightly over saturated. At the Daylight and Cloudy settings colors are a bit warmer than they ought to be and images shot at the incandescent (tungsten) setting show a noticeable and consistent orangeish cast.

Sensitivity

The Canon PowerShot SD870 IS provides an excellent range of sensitivity settings including - Auto, High ISO Auto, 80 ISO, 100 ISO, 200 ISO, 400 ISO, 800 ISO, and 1600 ISO. The tiny high pixel density sensor arrays found in consumer digicams generate more image noise than larger less crowded sensor arrays (like those found in dSLRs). Built-in noise reduction (NR) blurs away the worst image noise, but (depending on how aggressively NR is applied) it can also blur away important image detail. Canon’s SD family has one of the most aggressive noise reduction systems I've seen to date - images shot at ISO 80 show extremely low noise levels (ISO 100 images are identical to those shot at ISO 80) and very impressive resolution. At the ISO 200 setting noise levels (and detail loss) begin to rise a bit, but the images are still very good to excellent. ISO 400 images are noticeably noisy and detail loss is obvious, but they still usable in non-critical applications. ISO 800 images have a soft "look" and flat almost pastel-like colors – useful only for e-mail and web applications. ISO 1600 images are useless.

In-Camera Image Adjustment

In-camera image adjustment capabilities are often overlooked by casual shooters, but experienced users know the ability to make subtle color/contrast/sharpness/exposure adjustments is a very important creative tool and a simple and effective way to overcome minor exposure problems. The SD870 IS provides shooters with a helpful range of creative photo tweaks that can be applied in-camera, as opposed to more complex (and time consuming) post-exposure processing.

Very light or very dark subjects can trick light metering systems into underexposing or overexposing images. The SD870's Exposure Compensation mode allows users to subtly modify exposure parameters over a 4 EV range (+/-2 EV in 1/3 EV increments) to compensate for difficult lighting, back lighting, and subject/background reflectance/non-reflectance problems or to compensate for environmental exposure variables.

Canon's My Colors mode permits users to adjust color saturation, select Positive Film (mimics slide film color, saturation, and contrast), Lighter Skin Tone, Darker Skin Tone, Vivid Blue, Vivid Green, Vivid Red, Color accent (shifts images to B&W, except for one user selected color), color swap (allows users to switch one color for another), custom color (users can adjust color balance for red, green, blue, and skin tones over a +/-2 step range in 1 step increments), and Photo effects mode (vivid or neutral color saturation, low sharpening, sepia, and B&W), and touch up images in-camera (post exposure).

DESIGN, CONTROLS, ENGINEERING, & ERGONOMICS

The SD870 IS bears a strong family resemblance to the SD850 IS (and to the other members of Canon’s SD tribe) but it’s a tad heavier and marginally larger than its predecessor. The SD870 IS’s pocket-sized metal alloy body exudes an aura of toughness and durability, but the wrist strap should be used at all times – small smooth contoured cameras are easy to drop. The SD870 IS’s controls have been shuffled around to make room for the larger LCD screen, but camera operation remains logical and all controls are easily accessed, however the rotary jog dial around the compass switch takes a little getting used to. Those familiar with earlier digital elph models will have no problem using the SD870 IS without resorting to the directions and even rank beginners should be able to shoot decent images after a short familiarization run with the camera and a quick scan of the user's manual.

Technical Specifications

Resolution: 8.1 Megapixels (3264 x 2448)
Viewfinders: 3.0” LCD screen
Zoom: f2.8-f5.8/4.6mm-17.3mm (28mm to105mm - 35mm equivalent)
Auto Focus: Contrast Detection 9 AF point AiAF
Manual Focus: no
Flash: Built-in Multi-mode
Exposure: Auto and Program AE
Metering: Evaluative, Center-weighted, & Spot
Exposure compensation: Yes +/- 2 EV in 1/3 EV increments
White balance: TTL Auto, and 6 user selected pre-sets
Sensitivity: Auto, High ISO Auto, 80, 100, 200, 400, 800, and 1600 ISO
Image Storage Media: SD, SDHC, & MMC cards
Connectivity: USB 2.0HS, AV/out, & DC in
Power: NB-5L 3.7V 1120mAh Li-ion rechargeable battery

Included

32MB SD "starter" card, NB-5L Battery, battery charger, wrist strap, USB & A/V cables, software CD's, printed user’s and software manuals.

Optional Accessories

HF-DC1 slave flash unit, Canon WP-DC9 waterproof case, AC adapter, and Canon soft camera case.

In the Field/Handling & Operation

I regularly get together with an old friend who sells new and used photographic equipment. He shares my passion for photography (between us we have more than fifty years of photographic experience). We both love testing new photography toys, so when he stopped by to see if I wanted to help him put Canon’s new PowerShot SD870 IS through its paces – I jumped at the chance.

The first thing we did was to run some color tests. We use a homemade macro stage and a selection of brightly colored (red, green, yellow, blue, orange, and purple) plastic children’s beach toys arrayed on a white paper background. This test allows us to check color accuracy and the precision of the camera’s white balance system (and compare the results from camera to camera). The SD870 produced images that were dependably hue accurate, but noticeably over saturated.

After we finished our color/White Balance tests, we headed for nearby Cave Hill Cemetery. Cave Hill is Louisville's unofficial arboretum and a fine example of 19th century landscape architecture. Cave Hill’s 300 acres are home to a stunning variety of native and exotic trees, bushes, shrubs, and flowers. There are also thousands of old hand-carved native limestone grave markers, hundreds of elaborate mausoleums, a rustic old groundskeeper's cottage. Flocks of semi-tame ducks, geese, and swans fill the small lake (and its periphery) at the center of the cemetery.

After a summer long drought there wasn’t much autumn color, and what there was seemed limited to individual trees scattered about here and there – no grand fall color vistas. Louisville is usually very pretty in the autumn and since we’d finally gotten rain both of us had hoped that the trees would all start showing some color spontaneously, but our forlorn hopes were destined to be dashed. The weather was fairly warm and the skies were blue and after a couple of long loops through the oldest section of the cemetery we were able to shoot some individual trees, a few weather worn and time tilted old headstones, and a huge mixed flock of ravenous (and slightly aggressive) ducks, geese, and swans.

For our second outing with the SD870 IS we decided to shoot some action at Louisville's Extreme Park. We often test digital cameras (in addition to the SD870 IS we were also testing a Panasonic FZ18) at the Extreme Park because skateboarders and BMX bikers love to show off for the camera. We had to move in pretty close because the SD870 IS's 3.8X zoom was just too short to allow us to stand off at a safe distance and still get frame-filling shots (the FZ18’s long zoom and EVF provided way more framing and composition options). We spent a couple of hours shooting BMXers and skateboarders – we usually pick a spot where there is lots of activity, frame the composition, and then pre-focus on the spot where the action will peak. The SD870 IS's snappy performance, dependable IS, and a little luck got us a couple of fairly pretty decent mid-air shots.

After we finished up at the Extreme Park we headed for the Germantown and one of Louisville’s oldest neighborhood taverns - Check’s Café has been a local landmark since before WWII. Both of us are big fans of traditional Kentucky White Bean Soup and Check’s is famous for their Bean Soup. We got a couple bowls of steaming soup and a couple of cokes and found a corner table. Old neighborhood bars are a real challenge to photograph and Check’s dark (recently remodeled) interior was no exception. With the SD870 IS (in program mode - flash disabled and hi-ISO sensitivity enabled) we were able to sneak a few shots of the old tavern’s classic blue-collar ambience and a couple of the more interesting patrons. It was easy to keep the diminutive SD870 IS hidden, but our natural light indoor images were (not surprisingly) sort of dark and flat with lots of noise.

PERFORMANCE

Image Quality

We reviewed our images on a NEC Multi-sync XV 19" CRT monitor. Outdoor images shot at ISO 80 and ISO 100 were dependably sharp with bold color and they were essentially noise free. I would have liked to see Canon start the SD870 IS’s sensitivity range at ISO 50 or ISO 64, rather than ISO 80, since the camera’s ISO 80 and ISO 100 images are indistinguishable. Noise levels begin to rise after ISO 100. ISO 200 images are very good, but show some minor loss of detail and very slight but visible noise. ISO 400 images are noisy and look a bit soft, but they do seem better than the ISO 400 images from earlier digital elphs. ISO 800 images are very noisy, but they should be OK for non-critical 3x5 or 4x6 prints and for e-mail photos. ISO 1600 images are basically useless.

Native colors (typical Canon color interpolation) are bright, hue accurate, and natural-looking, but visibly over-saturated. Shadow detail capture is very good and the SD870 IS’s dynamic range is wider than average for this class of digicams. Chromatic aberration (purple fringing) is slightly lower than average, but corners are soft across the board. The SD870 IS, like many of Canon’s consumer level digicams, has a consistent tendency toward minor over exposure and burnt out highlights.

Timing/Shutter Lag

The Canon PowerShot SD870 IS is pretty quick for an ultra-compact digicam and that's primarily due to its third generation DIGIC processor. The boot-up cycle (about 1 second), shutter lag (1/10th of a second – according to Canon), shot to shot times (1.5 seconds), and write to card/processing times (about 2 seconds) are all quicker than average. With pre-focus AF lag essentially disappears and from scratch the SD870 IS needs less than half a second to lock focus and fire the shutter.

A Few Concerns

The SD870 IS (like all ultra-compact digicams) has red-eye problems - with cameras this small it is just not possible to physically separate the flash and the zoom sufficiently to avoid having both on essentially the same plane. I like large LCD screens, but with the SD870 IS’s 3.0 inch LCD being the camera’s sole viewfinder - I’d have given it up (in favor of a smaller LCD) for an optical viewfinder.

Conclusion

Back in the old days photographers who wanted an ultra-compact camera bought a Stecky, a Minox, or a Mamiya 16 - but today’s consumers have lots of pocket picture machine options. Canon’s Digital Elph series is probably the best of those many choices. Canon is well known for making tiny cameras that produce consistently super pictures with very little effort on the part of the photographer and the SD870 IS continues that worthy tradition. The SD870 IS should appeal to weight conscious travelers, gadget loving guys and gals, backpackers, budget savvy family photographers, and casual shooters who value compact size and auto everything operation.

Links

For definitive advice on How to Choose a Digital Camera please see my (updated) review:
http://www.epinions.com/elec-review-2E46-17B174E2-39A418E3-prod1

Canon Digital Rebel XTi/EOS 400D
http://www.epinions.com/content_257380814468

Canon Powershot A650 IS
http://www.epinions.com/content_404205833860

Canon Powershot S5 IS
http://www.epinions.com/content_378798313092