Higher-Resoluton ProRes Recording Will Provide Best Quality for UHDTV Programming, Company Says

ARRI continued to expand its 4K acquisition strategy this week with the announcement of ProRes 3.2K, a new Alexa recording format designed to allow easy, high-quality upsampling to UHD (3840×2160) resolution in post. The new format, conceived for television shows that require UHD delivery, is similar to the previously introduced Open Gate format for feature films, which records the full 3.4K image of the Alexa XT sensor for later upsampling to 4K (4096×2160) and output as a DCP.

ARRI said "most" available lenses cover a large enough image circle to be compatible with the 16:9 ProRes 3.2K format, which will be available for Alexa XT cameras as well as Alexa Classic cameras with the optional XR Module. The format will be enabled through a software update in early 2015, ARRI said.

ARRI has long argued that the Alexa is a future-proof camera, especially in the face of marketing pressure from competitors claiming full 4K resolution, and higher, in camera. "Designed from the outset to be adaptable and future-proof, Alexa can easily accommodate productions that choose to follow a UHD or 4K workflow," said Alexa Product Manager Marc Shipman-Mueller. "The camera's stellar overall image quality in combination with ProRes 3.2K or ARRIRAW Open Gate allows for simple upsampling to UHD or 4K in a quality at least as good as other contenders."

Indicating that the company is feeling some pressure to clarify 4K and UHD workflow, ARRI announced just last week that its Amira, a lightweight variant on the Alexa aimed at fast-paced documentary-style shoots, would be able to record ProRes upscaled to UHD resolution in camera. Users of the Alexa, however, are expected to integrate any required 4K or UHD upscale into their post-production workflows.

Recommended Alexa Recording Formats  
HDTV ProRes HD, ProRes 2K, or DNxHD
2K feature film ProRes 2K, ARRIRAW (16:9 or 4:3)
UHDTV ProRes 3.2K
4K feature film ARRIRAW Open Gate
Source: ARRI

On the feature-film side, ARRI noted that Skyfall was shot in ARRIRAW 2.8K and upsampled to a 4K DCP before the 3.4K Open Gate recording format was available. The company said Warcraft, San Andreas, Pixels, Goosebumps, and Sicario are currently shooting with Open Gate, while Terminator: Genisys, The Fantastic Four, Agent 47 and Deus Ex Machina are using Open Gate for VFX shots.