Panasonic's 2011 entry compact — 12MP CCD travel zoom, not the full-frame S1.
The 2011 Panasonic Lumix DMC-S1 is a budget 12.1MP pocket compact with a Leica-branded 4x zoom — an entirely different camera from the 2019 full-frame Lumix S1 that reused the name.
It offers a 28-112mm equivalent lens with optical stabilisation, 720p video, and simple intelligent-auto operation aimed at first camera buyers.
Its place in the catalog matters mainly for disambiguation: used listings titled 'Lumix DMC-S1' are this £20-40 compact, and mixing them into the full-frame S1's price data wrecked that master's median.
Working examples are cheap and plentiful; check lens extension, LCD condition and battery health — repairs exceed replacement cost.