Arri Alexa is the first out-an-out film-style digital motion picture camera system from the house of Arri. It was first introduced in April 2010 marking the entry of Arri into its first key transition into digital cinematography after smaller efforts such as the Arriflex D-20 and D-21 made previously. Features to be found on an Arri Alexa camera includes modularity, PL mount lenses, a Super-size 35 CMOS sensor with capability to shoot up to 2880 x 2160 resolution. The Arri Alexa is also known to support uncompressed video or also known as its proprietary raw data by the name of, ARRIRAW.
The is a raw codec that bears semblance to the CinemaDNG and consists of unaltered Bayer sensor information on it. The data stream from Arri Alexa camera can also be recorded via a T-link with the help of certified recorders like Codex Digital or Cineflow.
Arri Alexa comes equipped with an SxS card encoder which is capable of recording in Rec. 709, Log-C, ProRes 422, ProRes 444 codecs and DNxHD in 1080p resolution. However, after shelling out an additional 1,350 Euros on their Arri Alexa, owners can also purchase a software “key” through which they can unlock the ability to record in up to 120fps in ProRes 422 HQ on their cameras.
Arri Alexa camera is designed for use in big budget feature films, television shows and Ad Films, and is considered to be Arri’s attempt to respond to the growing demand for Red One camera series. There are also lower resolution cameras like the Sony CineAlta (35 mm, 1080p), Panavision Genesis (35 mm, 1080p), Thomson Viper FilmStream (2/3″, 1080p) built on same underlying principles of digital motion picture camera system to shoot feature films.
Arri Alexa Aleva III sensor: The ALEV III sensor featuring in the Arri Alexa uses 3392 × 2200 effective pixels for image generation, but only 2880 × 2160 pixels are used for recording in 4:3 mode on Alexa Studio and M, and further reduces pixels to 2880 × 1620 in 16:9 recording mode for the regular Alexa and other Arri models. The rest of the pixels are merely used to explore the elements present in the viewfinder.