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Canon surprised many industry observers by replacing the 14-megapixel PowerShot G10 with the 10-megapixel G11 model. However, this move makes sense because image noise was an issue with the G10 at ISO 400 and most photographers should appreciate having fewer - but larger - photosites that deliver better image quality. Nevertheless, the sensor remains pretty small (7.6 x 5.7 mm) and, more surprisingly, the RRP has risen by $150 since the G10 was released.

The new model retains the classic rangefinder styling of its predecessor and has the same optically-stabilised 6.1-30.5mm f/2.8-4.5 lens, which covers a 5x optical zoom range equivalent to 28-140mm in 35mm format. A larger font size has also been used in the model name. Both models have the same facilities for fitting adaptor lenses and accept the same LA-DC58K adaptor, which is used for attaching the optional TC-DC58D 1.4x teleconverter lens.

Front views showing the PowerShot G11 (left) and the G10 it replaces (right). (Source: Canon.)

The most obvious change to the body styling is the replacement of the fixed, 3-inch monitor on the G10 with a slightly smaller (2.8-inch) but vari-angle LCD screen. This monitor swivels out through approximately 170 degrees and rotates through 180 degrees for high- and low-angle shooting. It can also be positioned against the camera with the screen facing outwards for normal shooting. Resolution remains the same at approximately 461,000 dots.

Rear views showing the PowerShot G11 (left) and the G10 (right). (Source: Canon.)

Some minor, mainly cosmetic, changes have also been made to the top panel. One of the most useful has been to change the on/off switch from a rectangular button that sits slightly proud of the camera body to a circular button which lies flush with the top panel and is less easy to switch on accidentally. ISO settings have been expanded to include 3200, which was previously only accessible as a Scene preset.

Top views showing the PowerShot G10 (left) and the G11 (right). (Source: Canon.)

Other new features include a Dual Anti-Noise System, which has allowed Canon to raise the G11's ISO range to 3200. It's part of the DIGIC 4 Noise Reduction technology, which has been optimised for the new sensor. Canon claims it provides up to two stops improvement on the previous model at the same ISO settings. This improvement has led to some changes in camera performance.

In the Auto ISO mode, the maximum sensitivity has been raised from ISO 400 to ISO 1600, while with flash, the maximum sensitivity is increased from ISO 250 to ISO 800, extending the flash distance and providing scope for brighter backgrounds in flash shots. Dynamic range in shots is claimed at four times greater than the G10, reducing the incidence of blown-out highlights and blocked-up shadows.

The ISO 3200 Scene preset in the G10 has been transformed into a special Low Light mode, which is accessed via the mode dial. Instead of restricting users to ISO 3200, this setting will automatically set the camera to between ISO 320 and ISO 12,800, albeit with a reduced resolution of 2.5 megapixels. This is achieved adding four pixels - two horizontally and two vertically - in frame readout mode (1/4 still image).

Unfortunately you have no control over ISO settings in this highly-automated mode.  We discovered this when we used this mode late one evening, hoping to explore some really high sensitivity settings. Despite our attempts to extend its capabilities, the review camera refused to move beyond ISO 3200, regardless of how dark the subject was.

Another new addition to the mode dial is the Quick Shot mode, which sets the AF mode to continuous and displays a shooting data screen on the monitor. Pressing the Func/Set button lets you select individual items to adjust with the arrow pad. The illustrations below show the displays.

The monitor display in Quick Shot mode.


Adjusting settings in Quick Shot mode.

This user interface attempts to replicate the user interfaces in many entry-level DSLRs. It works reasonably well for the settings normally accessed via the Func/Set button. However, you must compose shots with the viewfinder when you use this mode. In addition, because the camera continuously readjusts focus and exposure until the shutter is half-pressed, power consumption is increased.

The range of the built-in flash is slightly greater than the G10's, probably as a result of the more sensitive imager chip. The G11 also supports flash synchronisation speeds of up to 1/2000 second when the Safety FE function is switched to on. In previous models, fill-flash shooting in backlit scenes was limited to a maximum shutter speed of 1/500 sec, which could result in overexposure. However the new model provides automatic flash synchronisation in response to the scene.

Canon's Face Detection AF/AE/FE/WB system has been improved and now automatically detects up to 35 faces within a frame before adjusting focus, exposure, flash and white balance to provide correct exposures. It can also determine which faces should be the subject and reverts to the 9-point AiAF system if no face is the primary subject. Detection angles have been increased, enabling partial profiles to be recognised.

Otherwise, very little has changed. The menu and Function menus are almost identical -although the highlight colour is now orange instead of red. White balance presets and fine-tuning are unchanged and white balance bracketing is still absent - although you can bracket exposure and focusing.

The built-in ND filter is still available and provides a 3-stop cut in in-coming light, allowing users to shoot with slower shutter speeds or smaller aperture values than the ambient lighting demands. Exposure compensation of +/- 2Ev is still available for both normal and flash exposures.

A few G10 functions have been removed, among them the Auto ISO shift, remote capture support and voice recorder. Battery capacity is also slightly lower at 390 shots/charge, compared with the G10's 400 shots/charge. The G11 accepts almost all of its predecessor's accessories - save for the underwater housing.

Sensor and Image Processing
The G11 replaces the G10's 14.7MP sensor with what it describes as a high sensitivity 10 MP CCD.  From its specifications, it looks like the new ICX685CQZ  CCD chip from Sony Semiconductor, which is also used in the S90. Developed to provide high sensitivity and wide dynamic range, it boasts 2.03 micron square photosites and has a diagonal measurement of 9.31 mm.

The manufacturer claims a one-stop improvement in the signal-to-noise (S/N0 ratio for the luminance signal. This is bolstered by a doubling of the sensitivity and 1.7x boost to the saturation signal which, together, increase the sensor's dynamic range.

Coupled to this chip is Canon's DiG!C 4 image processor, which was also used in the G10. Driven by advanced image processing algorithms, this chip manages all of the camera's primary functions and underpins the Dual Anti-Noise System, i-Contrast, Face Detection AF/AE/FE/WB and Scene Detection Technology.

 If we compare the last three G-series models, the following points of difference are noteworthy:

The G11 supports all of the TruCapture functions introduced with the G10, including Servo AF, Face Detect Self Timer, Blink Detection and i-Contrast. It also underpins the top shutter speed of 1/4000 second, which is unchanged from the G10. The Superfine quality setting (which applied minimal compression) has been eliminated from the JPEG options, although the image size choices are unchanged. 

Like its predecessor, the G11 supports JPEG and raw file capture, along with simultaneous RAW+JPEG recording. As in the G10, this facility must be selected in the camera menu and the default setting is Large/Fine. Raw files are losslessly compressed while JPEG compression is relatively modest with the Fine setting, but heavier with the Normal mode. Typical image sizes are shown in the table below. 

Movie capture is unchanged from the G10, with neither widescreen nor High Definition video supported. As in the previous model, audio data is recorded monaurally and a Wind Filter is provided in the shooting menu to suppress unwanted noise. Typical video recording times for a 2GB memory card are shown in the table below.

The Colour Swap and Color Accent features are available in movie mode and the image stabiliser remains active. However, the optical zoom is disabled, leaving you with only the digital zoom option if you want to zoom in or out. Unlike the G10, the new model has no facilities for separate use as a sound recorder.

Playback and Software
Pressing the playback button switches the camera to play mode and displays the last shot taken. Users can navigate from one image to the next with the horizontal arrows on the arrow pad or by turning the Control Dial in either direction. The down button on the arrow pad allows shots to be deleted individually
Pressing the Display button toggles through four options: image only, simple shooting data, detailed data and focus check display. When detailed data display is selected, an over-exposure warning is also engaged. A brightness histogram is also provided.

Once you open the playback menu, you'll find slideshows with selectable transitions, individual image erasing and protection, rotation, My Category and DPOF tagging, iContrast adjustment, red-eye correction, trimming, resizing, My Colours adjustment and scroll display. You can also toggle the Resume setting between Last seen and Last shot.

Playback zoom is engaged via the zoom lever, with up to 10x magnification available and you can move from shot to shot at the zoomed magnification with the Command Dial surrounding the arrow pad. With movie playback you can trim unwanted frames from the beginning or end of a clip in playback mode.

The camera comes with Canon's Digital Camera Solution Disk Version 54.0, which contains Digital Photo Professional 3.7 and PhotoStitch 3.1 for Windows and Macintosh plus ZoomBrowser EX 6.4 for Windows and ImageBrowser 6.4 for Macintosh. A Software Guide and Personal Printing Guide are also provided.

Performance
The claimed improvements in low light performance were evident in our test shots from the review camera. So were the improvements in dynamic range across all light levels when the iContrast was set to Auto.  Autofocusing was as fast and accurate as on the G10 we tested and manual focusing was easy, thanks to the enlargement of the focusing frame. 

The built-in image stabiliser allowed us to use shutter speeds as slow as 1/3 second and achieve acceptably sharp picture for approximately 50% of shots.  (An example is shown in the Sample Images section below.) At 1/10 second, the success rate exceeded 90% of shots. Auto exposure performance was consistently good with most subject types.

Canon appears to have improved the lens/sensor performance in the new model because lateral chromatic aberration was consistently negligible in our Imatest test. Unlike the G10 we tested, we also found few signs of coloured fringing in test shots and shots appeared sharp edge-to-edge under most conditions.

Imatest showed resolution to be close to expectations for a 10-megapixel digicam when JPEG shots were analysed. As with the G10, CR2.RAW files from the review camera turned in superior performance, with best results coming from the middle-range focal lengths and relatively wide aperture settings. The graph below shows the result of our tests on JPEG files at different aperture settings.



Image quality remained relatively high right up to ISO 800. However, beyond that point, the superiority of raw files was evident as resolution of JPEG images plummeted. The graph below shows the result of our Imatest tests at different ISO settings for both JPEG and raw files.

Long exposures at night were noise-free up to ISO 400 and noise-affected at ISO 800 but printable up to A4 size. Some loss of sharpness occurred at this point as well. Beyond ISO 800, noise was quite visible and shots taken with the ISO 3200 setting were noticeably softened, although printable at snapshot size. No colour drifts were seen across the review camera's sensitivity range.

Flash exposures showed little noise up to ISO 800 but noise was evident at ISO 1600 and sharpness had declined by ISO 3200. However, image files were ‘cleaner' overall than similar shots taken during our G10 tests.

The auto white balance setting left traces of a green cast under fluorescent lighting and, as expected, failed to eliminate the orange cast that characterises incandescent illumination. Fortunately, the tungsten and fluorescent pre-sets corrected both colour casts effectively and manual measurement produced neutral colours under both types of lighting.

As expected, we found slight barrel distortion at the widest focal length setting but this had been corrected by the middle of the zoom range. Pincushion distortion at the longest focal length setting was barely detectable. Although it was possible to force the lens to flare, we encountered very few problems with backlit subjects when using normal shooting strategies. 

The test camera powered up in approximately one second. Autofocusing times were generally quite good. At the wide-angle setting, we measured an average capture lag of 0.3 seconds, which is half the lag time of the G10 we tested.  For telephoto shots, capture lag extended to an average of 0.6 seconds. Shooting with flash made only minimal changes to these times.

Pre-focusing reduced this delay to less than 0.1 seconds with both focal lengths. Shot-to-shot times averaged 1.5 seconds for JPEG files and 2.5 seconds for raw files. RAW+JPEG pairs could be recorded at 2.8 second intervals, on average.  It took 3.1 seconds to process each high-resolution JPEG image and just under four seconds for each raw file. A RAW+JPEG pair took 5.3 seconds to process.
Continuous shooting was not particularly fast, probably because some processing takes place as bursts are recorded. We captured a burst of 10 Large/Fine JPEGs in 7.4 seconds, but on swapping to shooting raw files, the camera slowed markedly after five shots. A five-shot burst was recorded in 3.8 seconds and took 5.2 seconds to process.

In RAW+JPEG mode, burst capture was even slower and we were only able to record five pairs of shots in 12.7 seconds. However, on-the-fly processing enabled the burst to be processed and stored within 4.6 seconds of the last shot being taken.

Buy this camera if:
- You want a compact digital camera that fits into a jacket pocket.
- You want effective image stabilisation for stills and video clips.
- You'd like most of the controls and functions offered in serious DSLR cameras.
- You're interested in shooting raw files.
- You require high resolution and low noise levels at ISO settings up to 800.

Don't buy this camera if:
- You'd like the ability to shoot HD video clips.
- You will only shoot JPEG files.
- You require high burst speeds and buffer capacity plus fast cycle times for processing shots.

IMATEST GRAPHS

For JPEG files.

For CR2.RAW files processed with Digital Photo Professional.

SAMPLE IMAGES

Auto white balance with incandescent lighting.

 
Auto white balance with fluorescent lighting.

 
6.1mm focal length, ISO 80, 1/318 second at f/6.3.

 
30.5mm focal length, ISO 80, 1/636 second at f/4.5.

Digital zoom; 30.5mm focal length, ISO 80, 1/636 second at f/4.5.

Close-up; 30.5mm focal length, ISO 200, 1/202 second at f/4.5.

Long exposure at ISO100; 15 seconds at f/2.8; 8.9mm focal length.

Long exposure at ISO 800; 15 seconds at f/4.5; 8.9mm focal length.

Long exposure at ISO3200; 8 seconds at f/6.3; 8.9mm focal length.

Flash exposure at ISO100; 30.5mm focal length, ISO 100, 1/60 second at f/4.5.

Flash exposure at ISO 800; 30.5mm focal length, ISO 100, 1/60 second at f/4.5.

 
Flash exposure at ISO 3200; 30.5mm focal length, ISO 100, 1/60 second at f/7.1.

 
Dynamic range expansion with iContrast; note the shadowed areas, which would normally be blocked up in shots from a small-sensor digicam. 30.5mm focal length, ISO 100, 1/251 second at f/8.

Wide brightness range subject without iContrast but using a high ISO setting to optimise dynamic range; 6.1mm focal length, ISO 1600, 1/101 second at f/6.3.

The same subject with iContrast; 6.1mm focal length, ISO 400, 1/30 second at f/6.3.

Low Light mode; 30.5mm focal length, ISO 3200, 1/101 second at f/4.5.

Low Light mode with some subject areas in near darkness; 18.1mm focal length, ISO 3200, 1/50 second at f/4.

Image stabiliser test; 30.5mm focal length, ISO 400, 1/3 second at f/7.1.

Image stabiliser test; 30.5mm focal length, ISO 3200, 1/20 second at f/4.5.

Image sensor: 7.6 x 5.7mm High-sensitivity CCD with 10 megapixels effective
Lens:  6.1-30.5mm f/2.8-4.5 zoom (28-140mm in 35mm format)
Zoom ratio: 5x optical, up to 4x digital
Image formats: Stills - JPEG (Exif 2.2), CR2.RAW; Movies - MOV (Image Data: H.264; Audio Data: Linear PCM monaural)
Image Sizes: Stills - 3648 x 2736, 2816 x 2112, 2272 x 1704, 1600 x 1200, 640 x 480, Widescreen: 3648 x 2048; Movies - VGA/QVGA at 30 fps
Shutter speed range: 15 to 1/4000 sec.
Self-timer: Approx. 10 sec or 2 sec delay, custom, Face Self-Timer
Image Stabilisation: Optical (Lens Shift Type), approx 4 stops
Exposure Compensation: +/- 2 stops in 1/3-stop increments
Focus system/range: TTL Autofocus with Single, Continuous, Servo AF (with Servo AE), Manual; Face AiAF, Centre, Flexizone modes; Normal: 50cm - infinity, Macro: 1- 50cm (W), 30-50cm (T)
Exposure metering/control: TTL metering; Evaluative, Centre-weighted average, Spot modes
Shooting modes: Intelligent Auto with Scene Detection, P, Tv, Av, M, C1, C2, Low light, Quick Shot, Movie, Special Scene (Portrait, Landscape, Night Snapshot, Kids & Pets, Indoor, Sports, Sunset, Night Scene, Fireworks, Beach, Underwater, Aquarium, Foliage, Snow, Colour Accent, Colour Swap, Stitch Assist)
ISO range: Auto, ISO 80, 100, 200, 400, 800, 1600, 3200
White balance: Auto, Daylight, Cloudy, Tungsten, Fluorescent, Fluorescent H, Flash, Underwater, Custom 1, Custom 2
Flash modes/range (ISO auto): Auto, on, off, Red Eye Correction, Red Eye Reduction, Slow Synchro, Second Curtain Synchro, FE Lock, Safety FE; range - 50 cm - 7.0 m (W) 50 cm - 4.0 m (T)
Sequence shooting:  Approx 1.1 shots/sec; AF Approx 0.7 shots/sec; LV Approx 0.8 shots/sec.
Storage Media: SD/SDHC/MMC
Viewfinder:  Real-image optical zoom viewfinder with dioptric adjustment
LCD monitor: 2.8 inch vari-angle LCD monitor (approx. 461,000 dots)
Power supply:  NB-7L rechargeable lithium-ion battery
Dimensions (wxhxd): 112.1 x 76.2 x 48.3 mm
Weight: Approx. 355 grams (without battery and card)