ARRI’s new Alexa SXT (Super Xtended Technology) offers ProRes 4K recording,
improved image quality, powerful colour management and three fully independent
With in-camera recording of ProRes 4K UHD (3840 x 2160 pixels) and ProRes 4K
Cine (4096 x 2637 pixels), Alexa SXT cameras are the ideal choice for productions
that need 4K UHD TV or 4K DCI cinema deliverables.
Alexa SXT cameras keep the acclaimed 3.4K ALEV III sensor of previous Alexas and
add the electronics of ARRI’s Alexa 65 camera. These high-performance electronics
combine the latest generation of FPGA processors with a fast internal backplane and
form the basis of a completely overhauled image processing chain, advanced pixel
correction and optional noise reduction. This results in a further improvement in
overall image quality. Like their XT predecessors, Alexa SXT cameras retain Open
Gate, 4:3 and 16:9 sensor modes, which can be recorded in ARRIRAW or ProRes.
Taking advantage of the extremely wide native colour gamut of the Alexa sensor,
the new advanced colour management engine allows greater control. A new type of
look file, the ALF-2 (ARRI Look File 2), contains an ASC CDL (Colour Decision List)
as well as a 3D LUT (Look-Up Table). The new colour management engine can
easily match the look of current Alexa cameras, but also provides the basis for
radically different looks. In addition, previewing of looks on set is improved,
including the option to use the wide colour gamut of Rec 2020 gamma, while dailies
creation is made more efficient and final grading made faster. ALF-2 files and the
tools that create them are compatible between Alexa SXT, Alexa Mini and Amira.
To further streamline on-set workflows, Alexa SXT cameras include three fully
independent HD-SDI outputs. This allows, for instance, a Log C image to be used to
show the director a pristine image with live grading, a clean Rec 709 image to be
fed to video village, and a Rec 709 image with status information overlays to be
displayed on the camera’s on-board monitor.
The first Alexa SXT cameras are planned for release around mid-2015; the full
range will comprise Alexa SXT EV, SXT Plus and SXT Studio models, replacing
current Alexa XT cameras (though the Alexa Classic EV model will remain in the