Concept of development
The PowerShot G series is highly acclaimed for its class-leading image quality for a compact digital camera, as well as high reliability required for professional use and advanced features for creative amateur photographers.
The PowerShot G7 (Photo 1), successor to the PowerShot G6, has a completely renewed design, CCD and lens as well as significantly enhanced features. The development concept is as follows:
A digital camera capable of becoming the new standard while continuing with the high image quality and high functionality of the PowerShot G series
Feature 1: High image quality
• CCD sensor with 10 effective megapixels (approx.)
The PowerShot G7 features a CCD with about ten million effective pixels, which, together with the Primary Color Filter, produces high resolution up to 3648 x 2736 pixels. This enables large prints up to A2 size. It has six recording pixel modes: Large, Middle1, Middle2, Middle3, Small and Wide, along with three compression levels for a total of 18 combinations.
• High-resolution 6x optical zoom lens
The PowerShot G7 has a new 35-210mm (35 mm equivalent) f/2.8-4.8 lens developed for the PowerShot G7 (Fig. 1). It uses a 7-group/ 9-element system including a double-sided aspherical lens. Aberrations are corrected by using a cemented doublet lens and high refractive index glass.
These lenses utilize Canon's ''SR Coating'' technology for the first time in a Canon compact digital camera, greatly reducing ghosts caused by internal lens reflections.
The lens, despite being a 6x zoom, collapses completely into the body.
Table 1 lists the focusing distances and fields of view, including those when using optical accessories.
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• Optical image stabilizer system
An optical image stabilizer, using a lens shifting perpendicular to the optical axis, is used to reduce the impact of camera shake on image quality. The use of digital technology has made it possible to provide stable control using a single chip to reduce the size of the IS control component.
• High-quality image processing with DIGIC III digital imaging engine
The newly developed DIGIC III digital imaging engine (Photo 2) provides higher image quality and faster processing than the DIGIC II. Furthermore, the PowerShot G7 has face detection function, low-noise signal processing for high ISO and double data rate (DDR) memory.
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• High-speed AF and precise AE/AWB based on iSAPS technology
Feature 2: Advanced functions
• Face Priority AF/AE
In addition to the 9-point AiAF and 1-point AF available with previous models in the PowerShot/ IXY DIGITAL series, the PowerShot G7 is equipped with Face priority AF.
When using ''Face priority AF'', the lens focuses on faces detected in the frame (Photo 3). If no face is detected within the frame, the PowerShot G7 automatically switches to normal AiAF (9-point). When FlexiZone is selected, and the SET button is pressed, the AF frame moves to the ''face'' within the frame.
Face priority AE controls exposure for the entire image giving emphasis to the face when using face priority AF. In conditions where the face appears darker due to being backlit, the flash is automatically activated.
• New shooting modes: Aquarium and ISO 3200
The new ''Aquarium'' shooting mode gives correct exposure and natural color of fish swimming in an indoor tank when shooting from outside the tank.
''ISO 3200'' provides ultra-high sensitivity equivalent to ISO 3200 by switching the reading of the charge from the CCD to high sensitivity mode. As the flash is not activated, this is perfectly suited to shooting in dark places where flash photography is not permitted. The recording pixel is, however, fixed at 1600 x 1200 (equivalent to M3).
• Safety zoom
Recently, most image sensors are in the 5-10 megapixel range, and the use of digital zoom does not necessarily lead to reduced image quality in most cases, depending on pixel and digital zoom settings set by the user.
Therefore, when operating the zoom function, the original specification of always pausing the optical zoom at the telephoto end has been changed. Depending on the number of pixels, it pauses in an area where image quality is not reduced, enabling more effective use of the digital zoom function (Fig. 2).
• Digital tele-converter
In addition to optional optical tele-converter available with the PowerShot G series, the PowerShot G7 has a integral digital tele-converter applying digital zoom for easier telephoto shooting. A certain magnification is set and the number of pixels usable in shooting is limited, but it is possible to easily obtain the same effect as an optical tele-converter.
• Continuous AF shooting
While the PowerShot S3 IS improves response on moving subjects by using AF in continuous shooting during the sports mode, the PowerShot G7 is able to provide continuous shooting with AF in modes other than sports mode.
• Safety FE
Using the flash in close-up shootings such as in macro photography can result in overexposure. By turning ''Safety FE'' on when using the flash in such cases, the PowerShot G7 automatically determines the optimal aperture and prevents overexposure.
• Color Retouching with My Colors
In addition to the existing My Colors function, the PowerShot G7 is also equipped with a new function, Color Retouching with My Colors, which enables colors to be customized during playback.
• My Category
The PowerShot G7 has a My Category function (Fig. 3) where an image's data (still images and movies) can be assigned a category and data in the specified category can be played back, printed, deleted or protected.
There are seven categories that can be selected (People, Scenery, Events, Categories 1-3, To Do).
• Long movie shooting
The PowerShot G7 is able to record longer movies by supporting SDHC memory cards.
While in the existing PowerShot G series cameras, continuous shooting of movies stops when the file size reached 1GB, this has been extended to 4GB in the PowerShot G7, making it possible to shoot 640 x 480 pixels movies at 30fps for more than 30 minutes continuously.
The PowerShot G7 also supports high-resolution 1024 x 768 pixels movies at 15fps.
* Recording stops after one hour even if the file size has not reached 1GB.
• Safety Shift function ensures optimum exposure control
• Ultra-High sensitivity ISO 1600
• Focused position display for checking the focus in shots taken
• Compact, high-efficiency light guide flash with first- and second-curtain sync
• Real-time histogram display
• Two bracketing functions (AE/Focus)
Feature 3: Comfortable operation
• ISO Speed Dial
ISO speed is often changed depending on the shot, and the PowerShot G7 is equipped with a dedicated ISO speed dial (Photo 4). As the dial enables more intuitive operation than the Function menu used in existing models, the PowerShot G7 is much more user-friendly. Furthermore, a real metal detent ball is used in the dial giving it a high-class analog clicking feel.
• Controller wheel
The PowerShot G7 employs a rotating controller wheel (Photo 5) like the PowerShot S80, but more operations are available (Table 2).
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• Image playback button
Like the PowerShot S80, the image playback button makes it possible to easily switch the power on and off and switch between shooting and playback modes by pressing the playback button, power switch or shutter button halfway (Fig. 4).
• Resume playback
The existing PowerShot G series cameras start playback from the last image recorded. However, giving consideration to user-friendliness, the specification was changed to start playback from the last image played back.
Similarly, playback of movies is started from the last scene displayed during the last playback.
• Large 2.5'' LCD monitor with wide viewing angle
The LCD monitor employs a large 2.5'' LCD panel with 100% picture coverage to allow the user to view the subject more clearly for easy framing. The number of display pixels has been increased to 207,000, providing extremely high definition.
In addition to the application of a non-reflective coating, the Quick-bright LCD switches to the highest brightness in bright surroundings, such as outdoors, where the LCD monitor is usually difficult to see. When the subject is not bright enough, for example in shooting at night, the Night Display function automatically brightens the subject on the LCD monitor.
• Twenty-five language support
The user interface (UI) supports 25 languages to enable as many people as possible to use their native language when operating the PowerShot G7 (Fig. 5).
• Hi-Speed USB 2.0 supported
• Customizable information display
• Level meter for setting the microphone level
Feature 4: Full range of printing features and digital communication
• PictBridge supported
In addition to supporting PictBridge standard, the PowerShot G7 also has the following functions unique to Canon.
· Paper size: 356 x 432mm
· Paper type: Fine art paper, semi-glossy paper
· Print layout: 35-image “contact sheet'' layout, 20-image index with shooting information
• Print/Share button
• Exif 2.2 supported
• ID Photo Print
• Movie Print
• The CANON iMAGE GATEWAY website can be used
Feature 5: Extensive system accessories
• Compatible with EX-series Speedlites and accessories
The PowerShot G7 has an accessory shoe and can be used together with EX-series Speedlites such as the 580EX, 430EX and 220EX.
• Optional wide converter and tele-converter
The PowerShot G7 can be used with the TC-DC58C (Photo 6) tele-converter for doubling the focal length or the WC-DC58B (Photo 7) wide converter for reducing the focal length by 0.75x.
• Waterproof Case
For the first time in the PowerShot G series, the optional WP-DC11 waterproof case (Photo 8) usable to a depth of 40m is available.
This issue of the Technical Report introduces the PowerShot G7. Table 3 shows the major specifications.
The PowerShot G7 Kit comes as shown in Photo 9. There is no recommended retail price.
