The Sony Alpha SLT-A33 and A55, are the first cameras to incorporate Sony's translucent mirror design. The Single Lens Translucent (SLT) cameras offer live view with full-time fast phase-detection AF whether in stills or movie shooting. This is achieved by having a fixed, semi-transparent mirror that redirects a small amount of light onto the AF sensor while allowing the rest through onto the main imaging sensor. The A55 is built around a 16.2MP sensor while the A33 features a 14.2MP unit. Both feature 3.0" articulated LCDs, full HD video recording and ISO sensitivity up to 12,800, while the A55 also features built-in GPS. As well as being highly innovative, both cameras are fast, responsive and capable of excellent image quality.