The Canon PowerShot G7 was announced prior to Photokina 2006 at a time when everyone thought the Japanese company had killed the G-series. To most people's surprise, the G7 was one of the four Canons at the launch graced with the new Digic III imaging processor. One of the main features was the new Face Detection engine. So how revved up is this G7?
Design
The PowerShot G7 looks every bit like that film camera you discarded some years back. The black chassis gives the shooter a classy feel and a retro shutter button reminiscent of the past completes the whole makeup.
The plastic tube holding the extending lens felt like the same material used for a high school telescope project. Click to enlarge.
Clearly, the G7 isn't for everyone, especially those who want to slip it into their pockets. Throw the 106.4mm by 71.9mm by 42.5mm, 356 gram shooter at someone and they might think you're hurling a brick in their direction. That said, the size and build of the G7 does give it a very solid feel and make it one of the smaller prosumer cameras out there. One thing that didn't go down well with us was the plastic tube holding the extending lens. It felt like the same material a high school student would use to make a simple telescope for an astronomy project.
You get two control dials on the top edge -- one for shooting modes and another for ISO selection. There's a hotshoe on the G7 so you can attach an external Speedlight EX flash unit (220EX, 430EX and 580EX) for more light. Like the PowerShot S80 and the EOS 30D, the G7 comes with a scroll wheel to navigate the camera's menu system and settings. All the buttons and controls on the G7 are clearly labelled and responsive. Our only quibble is the four-directional keys within the scroll wheel which are a tad too small. Depending on how you hold your camera, you may end up with accidental presses.
Canon did away with the swivel LCD screen on the G7, so if that's the main reason you're buying a camera you're better off with the PowerShot S3 IS. Otherwise the 2.5-inch panel has a wide-viewing angle and we could still see our pictures even under harsh sunlight. Alternatively, you can peep through the optical viewfinder though it would have been a bonus if we could see camera status information through this window as well.
The AV-out and USB connectors are on the right of the unit behind a hinged lid where your palm rests. Click to enlarge.
You can find the compartment for the Lithium ion battery and memory card on the bottom edge of the G7 like most other shooters. The camera shuts down when the compartment is opened, even if you are in the middle of a shoot. What's interesting is that when reactivated, it returns to whatever state it was in, for example at 6x telephoto setting, so you can continue shooting where you left off.
Features
The new Digic III imaging processor which powers the 10-megapixel PowerShot G7 promises faster processing speeds, lower power consumption, better noise reduction and a new Face Detection function. Other cameras that use Digic III (at the time of review) include the IXUS i7 Zoom, IXUS 900 Ti and IXUS 850 IS. Judging by the buzz, Face Detection could be the Next Big Thing after high ISOs in digital cameras, with Fujifilm already adopting a similar feature in its FinePix F31fd and FinePix S6500fd before Canon. In idle mode, the G7 is able to track up to three faces, nine if you half-press the shutter and keep them in focus.
There are limitations to Face Detection, such as when the faces are too small, large, dark or bright relative to the overall composition, or when your subjects are looking sideways, moving too fast, etc. In a real-world scenario, this feature is more suited for taking posed pictures than impromptu portraits. Amid all the bells and whistles of the new G7, we were disappointed that the 6x optical zoom begins from 38mm (35mm equivalent) where it should have been a 28mm wide-angle lens. Put nine people side-by-side in a room for a group shot and you'll wonder why Canon didn't fit a 28mm lens on this PowerShot instead.
Another quibble we have on the G7 is a slower aperture of F2.8 at wide angle, stopping down to F4.8 at maximum telephoto. Its predecessor, the PowerShot G6, trumps the G7 with a faster F2.0 setting.
The PowerShot G7 features optical image stabilisation and a maximum sensitivity setting of ISO 1,600 -- both of which are becoming de facto standards in most midrange consumer digital cameras. Using a lens-shift system, the image stabilisation can remain on all the time or activated only when the shutter button is pressed. In panning mode, the IS compensates for vertical motion, useful if you are shooting panoramic pictures.
For photographers who want to have more handling control other than the aperture-, shutter-priority and manual options, they can also customise the display options of the LCD. What comes in really handy is the live histogram to make sure the exposure is correct. Dig into the camera's menu and you can further configure individual settings to be saved under C1 and C2 on the mode dial.
There's also a shortcut button on the top left corner at the back of the camera which you can preset to access settings which don't have their own dedicated key. Options include resolution, image quality, white balance and light metering.
Another tiny feature which we found useful is the focus check option. You can toggle the display during image review immediately after a shot to show the magnified area of the autofocus frame and to check whether the image is in focus. You can also navigate to other areas of the picture using the directional keypad. The G7 supports the use of a wide and a teleconverter. The wide converter (WC-DC58B, AU$299) changes the focal length of the camera by a factor of 0.75x, while the teleconverter changes the focal length by a factor of 2x.
Canon includes support for SD high-capacity memory cards up to 4GB. You can record VGA movies at 30 frames per second for up to an hour or until your card runs out of capacity, whichever is earlier. According to the company, the 720mAh Lithium-ion battery pack can provide enough power for approximately 220 shots.
Performance
In our tests, we found the PowerShot G7's performance to be good. We disabled the startup themes and the unit powered up in 1.1 seconds. Shutting down was a hair longer at 1.2 seconds. We fired our first shot in 1.8 seconds and managed to shoot thereafter every 1.8 seconds without flash or 2.8 seconds with flash.
The zoom mechanism on the G7 was quiet and autofocusing in conditions with adequate lighting averaged a second, or less. Canon claims a continuous shooting rate of two frames per second but we managed to clock only 1.7fps using our Imation 1GB SD card at 10 megapixels (Fine compression).
Image Quality
Granted that most people don't shoot in RAW, it was still a disappointment that the PowerShot G7 records only in JPEG. That said, image quality from the G7 was generally acceptable. We began to see noise only from ISO 400, though that's still barely noticeable until you scrutinise the shot. At ISO 800, noise was clearly visible but it's at the camera's maximum sensitivity setting of ISO 1,600 that you find your pictures looking like they're coated with a layer of sand. Unless you intended it to be that way, we don't recommend that you shoot at ISO 1,600.
The camera's auto white balance worked fine under most lighting conditions except for tungsten where our pictures turned out with an orangey shade. Switching to the Tungsten preset solved the issue. In addition, we also noticed slight barrel distortion at the wide end.
