The original three megapixel PowerShot G1 was announced at Photokina 2000 (September 2000), just less than a year later (August 2001) they announced the four megapixel PowerShot G2 with a fairly significant range of improvements. A year after that at Photokina 2002 Canon announced the new four megapixel PowerShot G3, with a sleek new body design, new control layout and image processor and four times optical zoom lens.

Canon PowerShot G3 vs. PowerShot G2 (differences only)

 
Canon PowerShot G3
Canon PowerShot G2
JPEG format EXIF 2.2 EXIF 1.1
Lens 4x optical, 35 - 140 mm equiv. 3x optical, 34 - 102 mm equiv.
Lens max aperture F2.0 - F3.0 F2.0 - F2.5
Lens thread 58 mm with bayonet fitting adapter 58 mm with screw fitting adapter
Auto focus Center area AF
FlexiZone AF/AE (300+ areas)		 3 area selectable
ND Filter Internal, menu option None
Custom exposure modes Two (similar to user memory) None
Shutter speed 15 - 1/2000 sec ** 15 - 1/1000 sec **
Manual WB Two presets One preset
Orientation sensor Yes, with auto rotate No
Focus bracketing Yes No
Manual flash power Yes, 3 steps internal, 16 external No
Flash sync select Yes, 1st-curtain, 2nd-curtain No
Photo Effects Available in all modes Dedicated exposure mode
Time-lapse photography Yes, Intervalometer No
Continuous shooting 1.5 / 2.5 fps, up to 14 images 1.5 / 2.5 fps up to 9 / 5 images
Movie clips (320 x 240) Up to 3 minutes * Up to 30 seconds
Self timer 2 or 10 sec 10 sec
Playback zoom 10x (10 steps) 6x (2 steps)
Movie editing Yes, trimming No
Play / record Shooting priority Switched play mode
Settings adjustment Control dial on hand grip 4-way controller
My Camera menu Yes No
Weight (inc batt.) 481 g (17.0 oz) 510 g (18.0 oz)
Dimensions 121 x 74 x 70 mm
(4.8 x 2.9 x 2.8 in) 		121 x 77 x 64 mm
(4.8 x 3.0 x 2.5 in)

* Requires high speed CF card
** At certain apertures (G3 considerably better than G2 in this respect)

The PowerShot G3 also includes some new technologies Canon were keen to stress at the time of announcement:

  • DiGiC processor - a new processor which is responsible for CCD control, AE/AF/AWB, signal processing, JPEG compression, memory card control, LCD monitor display).
     
  • Intelligent Scene Analysis based on Photographic Space (iSAPS) - Camera uses variables such as focus distance, exposure brightness and cross references these against a large internal database of known scene types and uses this information to optimize image processing.
     
  • Flexible AF point selection - You can now select from any one of more than 300 positions around the image frame.