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Canon PowerShot G5 The next generation of Canon's popular "G" model updates the line with a larger, 5.0-megapixel CCD. Select a topic Reference: Datasheet G5 Photo Gallery! G5 Sample Images --------------------------------- 1. Intro and Highlights 2. Executive Overview 3. Design 4. Viewfinder 5. Optics 6. Exposure & Flash 7. Shutter Lag & Cycle Time Tests 8. Operation & User Interface 9. Camera Modes & Menus 10. Image Storage & Interface 11. Video, Power, Software 12. Test Results & Conclusion --------------------------------- Print-Friendly Review Version Additional Resources and Other Links Reader Comments on G5 Review --------------------------------- Digital Camera Comparometer (TM) --------------------------------- <-- Digital Cameras (Home) <-- Digital Camera Reviews Index <<Camera Modes & Menus :(Previous) | (Next): Video, Power, Software>> Page 10:Image Storage & Interface Review First Posted: 08/18/2003

Image Storage and Interface

The G5 uses CompactFlash memory cards for image storage, accommodating both Type I and II card sizes. This means that the camera is also able to store images to an IBM MicroDrive for increased storage capacity. A 32MB CompactFlash Type I memory card is supplied with the camera. Entire CompactFlash cards cannot be write-protected, however, the G5's Play menu allows you to write-protect individual image files, protecting them from accidental erasure, unless the card is formatted.

Still images can be saved at one of four resolutions (2,592 x 1,944; 1,600 x 1,200; 1,024 x 768; or 640 x 480 pixels), while movies are recorded at either 320 x 240 or 160 x 120 pixels. Still images also have three JPEG compression levels available: Superfine, Fine, and Normal, plus a RAW setting that records the image straight from the CCD, without any processing. The benefit of the RAW data file format is that it compresses the image file without any loss in image quality (that is, the compression can be completely reversed) and the color isn't adjusted to match any particular file format, such as RGB TIFF. All of the image color parameters are kept in their original state. (RAW images require the Canon Zoom Browser software for processing on a computer.)

Following are the approximate resolution / quality and compression ratios for a 32MB card (compression numbers are based on our own computations):

Image Capacity vs Resolution/Quality		Fine	Standard	Basic	RAW Format
High Resolution 2,592 x 1,944	Images (Size)	12 2.6 MB	22 1.4 MB	44 719 KB	6 3.9 MB
	Approx. Compression	6:1	10:1	21:1	3:1 (lossless)
Medium 1 Resolution 1,600 x 1,200	Images (Size)	30 1.0 MB	55 580 KB	109 294 KB	-
	Approx. Compression	6:1	10:1	20:1	-
Medium 2 Resolution 1,024 x 768	Images (Size)	54 593 KB	95 335 KB	174 184 KB	-
	Approx. Compression	4:1	7:1	13:1	-
Low Resolution 640 x 480	Images (Size)	120 265 KB	196 163 KB	341 94 KB	-
	Approx. Compression	3.5:1	5.7:1	10:1	-

A full complement of interface software comes with the G5, as does a USB cable for speedy connection to a PC or Macintosh computer. The G5 supports "PTP" image transfer mode, which means you can connect it to a computer running Windows XP or Mac OS X without the need for additional driver software. (Drivers are included for other flavors of Windows and Mac OS though, so no worries if your computer is running an older OS.) I measured the G5's transfer rate on my Sony Vaio desktop computer (2.4 GHz Pentium, Windows XP), and clocked it at 451 KB/second using the Windows XP photo download wizard, and 341 KB/second using Canon's ZoomBrowser software. While not terrible, these aren't especially impressive numbers, as the slowest cameras I test are rarely slower than 300 KB/second, while fast ones routinely put up numbers close to or above 600 KB/second.

Direct Print
Besides the USB computer connection, the G5 also supports direct printing (no computer needed) to a number of Canon printers. Models that can be directly connected to the G5 include the compact Card Photo Printer models CP-200, and C-300 (as well as the earlier CP-10 and CP-100), and the i70, i470D, and i450 (as well as the earlier S830D and S530D Bubble Jet (inkjet) printers. The Bubble Jet printers support the EXIF 2.2 standard, which takes advantage of special "metadata" stored in the JPEG file header to optimize print quality.