Sony has added an intriguing new feature to the α (alpha) digital SLRs announced at the PMA show in Las Vegas: live view. The 14.2-megapixel $900 DSLR-A350 and 12.2-megapixel $800 DSLR-A300 both allow the user to preview images in the LCD screen. The live view is made possible by a separate CCD imager built into the viewfinder prism. 
Both cameras have live view-enabled tilting 2.7-inch LCD screens with 230,000 pixels. According to Sony, the new feature (which they call Quick AF Live View) is made possible by a redesigned viewfinder and a separate image sensor that produces only the live view. This also allows the cameras to focus without having to flip up the mirror: other DSLRs that offer live view have to flip up the mirror, then focus the lens, which leads to a noticeable delay. The new Sonys can use this secondary image sensor to focus, so the lens is already focussed when the lens flips up tot take the photos. Read the whole article here.