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State of Imaging

With CMOS becoming a major force, it's time to update what is powering the great video we shoot every day.

The most interesting question is: Why does a smaller HDV or AVCHD camera with, say, a chip that is 1/6" in size, with over a million pixels packed onto it, have differences, both good and bad, versus a chip that is 2/3" in size, but is only considered standard-definition with about 320,000 pixels?

In a small, high-definition-resolution chip, the pixels are smaller and packed more closely together to fit onto the chip, leading to a lower signal-to-noise ratio than a standard-definition chip would have achieved. The result is that the bigger, standard-definition-resolution chip is more sensitive to light and has less visible noise in the image it reproduces.

Not all sensor sizes are native to the final aspect ratio they produce. The Canon XL H1 has three 1440x1080-pixel sensors, the Sony HVR-Z1 has three 960x1080-pixel native sensors and the Panasonic AG-HVX200 has three 960x540-pixel sensors, yet they are all capable of reproducing 1080i (1920x1080-pixel) video. Each camcorder is capable of doing this by a measure of multiple technologies and algorithms that include pixel shifting and pixel interpolati…