Know Your Formats, Part 1
Apr 14, 2008 12:00 PM, By Jan Ozer
The Pixel Side of the Story
There’s one big caveat, however. Just because the format can store the image pixel for pixel doesn’t mean that the camera can capture the image pixel for pixel. Hence the significance of the Required Pixels line in the features table.
For example, the Sony HDR-FX1 has three CCDs, each with about 1.12 megapixels, which is insufficient to capture HDV’s 1440x1080 resolution pixel for pixel. This means that Sony is capturing the image and scaling it up to 1440x1080 for storage, and that those pixels are further scaled up to 1920x1080 resolution during display. In contrast, the Canon XH A1 has three imagers capturing 1.67 megapixels each. Thus, it came as no surprise that the Canon produced noticeably better detail than the Sony in most tests.
The bottom line is that when shopping for camera gear, you should identify the pixel aspect ratio used in cameras that you’re considering. Understand that this varies in some standards—such as AVCHD, where my fun Panasonic AG-HSC1U captures at 1440x1080, while the newer Sony HDR-SR10 captures at true 1920x1080 resolution. Then be sure to check if the CCD or CMOS imagers on the camera have sufficient pixels to capture the required pixels, pixel for pixel.
That’s as much fun as I can squeeze into a single installment. In the next, I discuss the remaining items in the feature table.
