Sony's mid-range SLT with translucent mirror — 16.2MP APS-C with 10fps burst and GPS.
The Sony Alpha A55 was released approximately 2010 as an APS-C mirrorless camera using Sony's SLT (Single-Lens Translucent) technology — a fixed, partially transparent mirror that allows continuous phase-detect AF during live view and video recording without a movable mirror mechanism. Sony A mount.
16.2MP APS-C CMOS sensor. SLT translucent mirror technology — continuous phase-detect AF in live view and video. 10fps continuous shooting. 1080p/60fps video. Built-in GPS. Tilting LCD. At approximately 397g with battery. Sony A mount.
The SLT approach retained Sony A-mount lens compatibility while enabling video AF that phase-detect-based DSLRs of the era could not match using contrast-detect only. The translucent mirror diverts approximately one third of incoming light to the AF sensor at all times, slightly reducing light reaching the imaging sensor. A precursor to Sony's later full mirrorless Alpha FE system.
On the used market the Sony A55 is a vintage SLT camera for the Sony/Minolta A-mount ecosystem. Condition checks: SLT mirror for dust or cracks (the translucent mirror requires careful cleaning), shutter actuation count, tilting LCD hinge, GPS function. Sony A mount — Minolta AF lenses compatible.