SONY A55 TRANSLUCENT MIRROR
In a regular S.L.R. camera (single-lens reflex — those big black pro cameras), light enters the lens, hits a mirror and is bounced up to your eye and, simultaneously, onto a focusing sensor. Unfortunately, when you take the photo, the mirror has to flip out of the way so that the light falls on the image sensor (the “film”). At that point, the camera can’t focus. That’s why most S.L.R.’s can’t change focus during burst-mode shots, or while filming video.
Sony’s A55 camera ($850) solves that problem by using a translucent mirror. It splits light between the focusing sensor and the image sensor. The mirror never moves, so the autofocus never goes blind. The camera can take 10 shots a second, refocusing all the way — no other camera can do that — and change focus as you pan or zoom, gorgeously and cinematically. No wonder this was Popular Photography’s camera of the year.
Sounds very interesting. I wonder what the down side is.