We take a look inside Sony's new fixed mirror system.
While Sony uses the term “Translucent Mirror Technology” for its new Alpha 55 and 33, the mirror isn’t technically translucent. If it were, only diffused light, not detailed images, would pass through. Instead, most of the light passes through to the image sensor, and just a little reflects up to the AF sensor, allowing continuous phase-detection AF while shooting.1. APERTURE RING DRIVE MOTOR: This rotates the lensmount aperture ring to control the lens iris.