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Canon Power Shot G2 Camera Review

The G2 is not just a G1 with a greater matrix. This camera has wider functions and capabilities: three exposure metering modes: evaluative (new), center-weighted and spot, adjustable exposure/aperture in a program mode, the exposure range has grown from 8 to 15 sec, and the continuous shooting has changed from 1.7 to 2.5 fps, it's possible to choose one of three focus areas, view a histogram of a shot, a RAW shot can be converted to 8 or 16 bits. The components have also changed: it comes with a greater matrix with GRGB filters (instead of CYGM), a grip for the right hand. But the lens is the same. Will its optical qualities be sufficient for a 4 Mpixel matrix with a smaller step? The table below shows popular cameras which have these brandname bloomed lenses. They are successfully used in 4Mpixel cameras. The Casio 4000 has a smaller frame than the other models but the specified equivalent focal length is the same. It can be either because of larger cells of the matrix or wrong calculation of the focal equivalent (though it's unknown who calculates incorrectly). At the same time the whole matrix is 4Mpixel. Isn't it the lens that reduces the Casio's frame to 3.763 Mpixels and the Canon/Sony's one to 3.871? 

3 Mpixel camera
4 Mpixel camera
Carl Zeiss Vario-Sonnar f7-21, f:2-2.5, equiv. 34-102  Sony S75, 2048*1536, ISO 100 - 300, focusing range: 4 cm - infinity Sony S85, 2272*1704, ISO 100 - 300, focusing range: 4 cm - infinity
Canon Lens f7-21, f:2-2.5, equiv. 34-102  Canon G1, 2048*1536, ISO 50 - 400, focusing range: 6 cm - infinity Canon G2, 2272*1704, ISO 50 - 400, focusing range: 6 cm - infinity
Canon Lens f7-21, f:2-2.5  Casio QV 3500EX, 2048*1536, ISO100 - 500, focusing range: 6 cm - infinity, f equiv. 33-100 mm Casio QV 4000, 2240*1680, ISO100 - 500, focusing range: 6 cm - infinity, f equiv. 34 - 102 mm
Epson Digital camera Lens f7-21, f:2-2.5, equiv. 34-102  Epson Photo PC 3100Z, 2048*1536 (2544*1904 interp.), ISO 100 - 400, focusing range: 6 cm - infinity.   

The G2 has a larger frame and it's possible to see how the resolution changes as the chart moves to the frame's edge. It's possible to draw a diagram of resolution in lines per pixel as shifting away from the frame center, normalized for a half of a diagonal, for a radial resolution chart when shooting in transient light at T = 5000K. In some directions the resolution can be higher than shown on the diagram, but it was drawn for the value when all lines in all directions are well discernible and brightness levels of black/white lines are quite different.

For the wide-open shutter and the lens at f = 7 mm the resolution doesn't tend to fall down on the frame's edge as well. 

It's interesting to compare the resolution of this camera with that of a 3Mpixel one. The Sony S75 model was tested in almost the same conditions and its resolution in the frame center was 0.73. The Casio QV 4000 scored 0.72. That is why our lens is sufficient enough for the 4Mpixel camera of a 3.87 frame and a frame's linear size 10% greater as compared to the 3Mpixel camera. 

How strong are chromatic aberrations and geometrical distortions on the frame edge? Here is how the upper left-hand corner of the frame looks like for the lens in the W position at f:2 (scale 1:1):

The distortion is not great - the minimal diameter of the circular chart relates to the maximum one as 0.95. With the Levels program of Dmitry Kuznetsov we drew histograms of the circular chart's section for the frame center and edge at f = 7 mm and aperture f:2 (the horizontal linear size of the histogram corresponds to the radius of the circular chart of the upper frame). The contrast is noticed to be lower by the edge (the lower diagram in comparison to the upper one), and if the brightness difference ratio for the high frequencies to the lowest frequencies in the center (for the first well discernible ring) is about 0.2, it tends to be 0.08 near the edge. The optical properties of the lens do not worsen greatly near the edge. 



It's possible that it's not worth buying a more expensive 4Mpixel camera instead of its predecessor if the former has just a 10% larger (in diagonal) frame. However, the $200 difference also delivers better handling (in shrinked ISO settings range in case of Casio), advanced focusing and exposure systems and a higher speed. 

You can use optical attachments for the Canon G2 lens. Fortunately, it's not necessary to text in them in the menu like in Nikon. But it can be a problem to find an appropriate adapter for homemade or third-party attachments. The thread is external and it is hidden under the metallic lid inside the blend integrated into the lens body. The thread looks as it it's 46*0.75, but the standard diameter conversion rings for 46 do not fit. But if you find a right ring, you can screw on any attachment using color filter mounts.

The case of the camera is partly metallic, but there are plenty of plastic details as well. The mode switches and the rong with a zooming lever look a little flimsy. The management is carried out mostly with buttons. What is a real disadvantage of the G2 as compared with similar models from Casio and Sony is the necessity to use a 4-way joypad for a setting chosen with a button instead of a dial like on advanced film reflexes. But maybe it's just a matter of habit. Besides, you can't view a just made shot: you have to switch the record/playback mode but you can retain such a shot by pressing the SET button (and view a histogram as well) or by holding the release button. An external ring selector is used to switch to recording or playing and the inner dial allows choosing a shooting mode. There are exposure modes: manual, shutter and aperture priorities, program one allowing us to choose exposure/aperture (via expo-lock), automatic - green area. You can also shoot in one of the following modes: "pan focus" (W and a fixed focus from 65 cm to infinity), "portrait", "landscape", "night portrait", "color effects" (vivid, neutral, sepia, B/W), "panorama" in a column / row / 2*2, "video and sound". The upper panel also houses a button of "continuous shooting/self-timer/RC", an information display and a Canon's flash hot shoe. The left panel incorporates power, USB/printer and audio/video connectors and a manual focusing button. It fixes focusing when the auto focus works and displays the distance in meters and feet. At the distance of 3 - 5 m and more and focusing in bad conditions the indicator shows infinity, that is why it's not always possible to use the camera as a distance meter, though such solution (to set the lens to infinity) speeds up focusing in complicated conditions (at the expense of precision). The G2 has an G2 has an automaticaly powered on AF assist lamp, it's also a timer indicator. 

The G2 has a swiveling LCD display. You can shoot from any position. The frame rotation system works correctly in standard positions, but a manual management of reflection/rotation of frame on display would be a good add-on for shooting from a non-standard position or when optical attachments are used. In some positions (for example, when the display is turned toward the lens and an object) information is not displayed. When not in use or when an optical viewfinder is used, the display folded in is well protected. 

The back panel has the following controls: a 4-way selector and buttons: flash / multiple image modes, exposure spot metering, macro mode, focus area, menu, exposure parameters fixing, shooting corrections (expo, bracketing, white balance, flash pulse) and a display mode. Like in most digital Canon cameras, the exposure bracketing is based on the exposure correction. When white balance is measured manually the flash is accounted for if it's enabled and lighting is scarce. It also concerns fixing of exposure parameters. 

The exposure range of the G2 is not great: 15 s - 1/1000 s, and not all combinations of exposure/aperture are possible. Here are minimal exposure values at the following aperture: f/2 - f/3.2 - 1/500, f/3.5 - f/4.5 - 1/640, f/5 - f/7.1 - 1/800, f/8 - 1/1000. At the exposure greater than 1.3 s the noise reduction gets enabled. 

Menu settings

Focusing is made in the central area, macro mode, flexible program mode P, flash off, matrix metering, white balance - incandescent lamp (sunny, cloudy, two settings for daylight lamps, flash, manual metering and auto).
Video shooting. Zooming is impossible during shooting. In video and manual focusing the central part can't be enlarged as you can see on the photo - it's after editing. However it is so in photographing. The scale of the distance meter is divided in two: 10 cm - 1 m and 1 m - infinity.

Auto exposure bracketing is adjusted according to the exposure correction, in this case the correction is 0, bracketing is +-1.3
Menu of settings. I wish it were possible to turn off the system sound, and here you can only turn it down to get rid of the welcoming tune.

Flash pulse can be corrected +-2 
In the playback mode it's possible to view a histogram and shooting settings; overlit areas blink

Settings of size, resolution, sensitivity, zoom and focusing mode (continuous, single)
Printing menu. Apart from DPOF there is direct printing on the Canon CP10/100.

In the speed shooting mode "H" not every shot is displayed, a pair of shots is made in a less than second. Remember that contrast, sharpness and saturation settings are not set to default when the camera is turned off/on.
Multiple image mode. Viewing menu: protect, rotate (identified by the Canon's software), erase, slide show, DPOF

In case of the continuous shooting mode "H" without displaying each shot the camera records 3 - 4 shots in a burst into the buffer (JPEG 2272*1704, best quality, 1.5 MB). If exposure is short 3 shots are usually made during less than 2 seconds, if it's long (e.g., 1/8) - 4 shots are made as 2, plus 1s delay plus 2 more during 2 - 3 sec. After that 1 shot is made at 3 - 5 sec. It makes sense to shoot in the "H" mode only something moving too fast; usually a simple speed mode is enough.

The camera is powered by BP 511 or BP 512 rechargeable battery (the charger is in the camera). Of course they could use AA in such a huge case, but the time of running from 1 battery is really great. The external power is 9.5 V 2.7 A or 8 AA batteries via a non-standard connector. Such a powerful external source is necessary for prompt charging of the battery in the camera. It's also possible to make a selfmade accumulator emulation unit for the rechargeable battery - then 6 AA are needed. In the "city" mode we had no shooting problems with  the supplied battery during a month of working with the camera. According to http://www.dpreview.com/ the Canon Power Shot G2 (3.5 hours of shooting) work longer than Casio with 4 AA 1600 mAh and Sony with a NP-FM50 battery. That is why the external unit seems quite useless, except maybe for far traveling.

We had no shooting problems at all. The camera is a real ascetic (the timer is only for 10 sec, the exposure meter can be switched (evaluative/center-weighted) only via the menu, only three focus areas, user interface can't be adjusted) and looks reliable (as a digital one). The shooting process is handy, but you must remember that all settings remain after the camera is turned off. It's very useful if you know what you are going to shoot as you can make settings beforehand, but the camera quickly fished out of the box can have not the right settings you need at the moment. Possibility to shoot in RAW, the remote control and compatible flashes are all advantages of the Canon camera. But there are some downsides as well: threads for attachments, USB and power connectors, no information output in some positions of the display.

The software allows converting RAW (RAW Image Converter) into tiff or bmp and shooting via USB from a PC in the shooting mode (interval and delay) and with all main photo settings supported - RemoteCapture. The box also contains a USB driver, PhotoStitch 3.1 (panoramas), Zoom Browser EX. I promise to examine all that stuff in the next review of the G2.


Matrix CCD, 1/1.8",4.13 Mpixel
Exposure, aperture: 15 sec - 1/1000, f/2 (W) / f/2.5 (T) - f/8
file formats: RAW (8/16bit), JPEG EXIF DPOF, AVI320*240,160*120 15 fps
exposure: metering: evaluative (new), center-weighted and spot
modes: manual, shutter/aperture priority, program, auto, programs, exposure correction, exposure parameters fixing, with the flash as well.
focusing 70 cm - infinity, macro 6 (W) / 20 (T) -70 cm
auto 3 zones, manual
in macro mode 60*82 mm (W), 62*84 mm (T)
viewfinder, display optical viewfinder - 84% frame coverage, dioptre correction.
1.8", 113578 pixels, 270 degrees (horizontal) and 180 degrees (vertical)
flash: 70 cm - 4.5 m (W) / 3.6 m (T)
auto on/off, red eye reduction, manual pulse adjustment, FE-Lock
external compatible E-TTL/ZOOM flashes: Canon Speedlite 220EX, 380EX, 420EX, 550EX, MR-14EX. Minimal exposure with flash - 1/250 s 
storage: Compact Flash Type I / II / Microdrive 
interfaces: USB, IR-RC, NTSC/PAL video minijack
power: Li-ion battery BP511 (512) 7.4 V, 1100mAh
external unit - Canon CA560 9.5 V 2.5 A 
dimensions: 120.9*76.6*63.8 mm, 425 g without battery
Sergei Shcherbakov (sherbakovs@rambler.ru)


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