Arri Alexa

The Arri Alexa (stylised as ALEXA) is a digital motion picture camera system made by Arri first introduced in April 2010. The camera was Arri's first major transition into digital cinematography after smaller previous efforts such as the Arriflex D-20 and D-21. It features modularity, PL mount lenses, a Super 35 sized CMOS sensor shooting up to 2880×2160 (2K) resolution and supports uncompressed video or proprietary raw (ARRIRAW) data.

The camera has several methods of recording, including SxS cards, CFast 2.0 cards and SXR Capture Drives at resolutions up to 2880 x 2160 pixels in either Rec. 709 or Log-C to ProRes or ARRIRAW codecs. Alexa camera owners can purchase additional software licenses that will unlock different capabilities of the Alexa Camera including High Speed 120fps recording, DNxHD codec and 4:3 "Open Gate" Mode for anamorphic lenses.

The camera is designed for use in high budget feature films, television shows, and commercials, and competes with Red Digital Cinema's line of high end cameras such as the Epic Dragon and Weapon Dragon.

The range of Alexa models has expanded over time:

The first camera of the Alexa product family. The ARRI ALEXA’s CMOS Super-35mm sensor is rated at 2.8K and ISO 800. That sensitivity allows the camera to see a full seven stops of over exposure and another seven stops of underexposure, an unprecedented Dynamic Range. To take advantage of this, ARRI offers both industry-standard REC709 HD video output as well as the Log-C mode that shows the entire range of the chip’s sensitivity, allowing for an extreme range of color correction options in post.

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