Sony's second-gen low-light specialist — 12.2MP full-frame with IBIS, internal 4K, and S-Log3.
The Sony α7S II (ILCE-7SM2) was released in 2015 as the second-generation full-frame video-optimised mirrorless for Sony FE-mount, adding 5-axis SteadyShot INSIDE IBIS (4.5 stops) and internal 4K recording over the original A7S. 12.2MP full-frame sensor with enlarged photosites for extended low-light range. 4K UHD/30fps internal. NP-FW50. At 627g with battery.
12.2MP full-frame CMOS (35.6×23.8mm, enlarged photosites for low-light). 4K UHD (3840×2160) at 30fps internal (XAVC S or AVCHD). 1080p/120fps. 5-axis SteadyShot INSIDE IBIS (4.5 stops, CIPA). ISO expandable to 409600. NP-FW50 battery. Approximately 627g with battery. Sony FE mount (full-frame).
The A7S II's 12.2MP sensor uses enlarged photosites for extended low-light range: the resolution trade versus 24MP or 42MP sensors is intentional, prioritising per-pixel light collection. The 5-axis IBIS was the primary upgrade over the original A7S (which had no stabilisation). Internal 4K was added — the original A7S required an external recorder for 4K.
On the used market the Sony α7S II is available at second-generation FE video body pricing. Condition checks: NP-FW50 battery health, IBIS operation (5-axis), 4K recording function. Note: 5-axis IBIS confirmed at 4.5 stops — some sources incorrectly state no IBIS. Compatible with all Sony FE-mount lenses.