The SX170 IS is much the same as its SX160 IS predecessor with a 16x optical zoom and 16 megapixel CCD sensor, though it's no longer powered by AA-batteries. It now offers a rechargeable lithium-ion pack, and the compact super zoom is overall slightly lighter and smaller than the SX160 IS. The SX170 includes 32 predefined auto settings that it can select for you. Alternately, it offers program, shutter priority, aperture priority, and manual modes for more control.